Best 11 Freshwater Fishs for Newbies 2024

If you’re getting into freshwater aquariums for the first time, it can be intimidating to know which fish to pick. Ideally, you want something hardy, budget-friendly, and colorful with an interesting personality. Check out our list of top 20 beginner fish (in no particular order) that are easy to care for and would make a great addition to your aquarium!

1. Platy fish

The Platy is an easy-care fish perfect for beginning aquarists. Also known as the Moonfish or the Southern Platyfish, the popular Platy comes in many color and fin variations, the most common being a solid, and brilliant red. Some Platy variations include Wagtail, Blue, Simpson Tuxedo, and Simpson Coral Platy to name a few.

The Platy adds brilliant color to the aquarium and they are very easy to keep. These features make it a great fish for beginners and accomplished aquarists alike. The Platy requires an aquarium of at least 10 gallons that is densely planted with hardy plants like Java Fern and Java Moss. The Platy is a very peaceful fish and makes an excellent addition to the freshwater community aquarium. Any other peaceful fish can be housed with them

The Platy is a livebearer and is capable of reproducing at three to four months of age. The male is smaller and more brightly colored than the female, and can be distinguished by his gonopodium. The fry will most often reach maturity in a community aquarium.

The Platy is an omnivore that will eat commercially prepared flaked foods and algae, as well as freeze-dried bloodworms and tubifex, and brine shrimp.

What are the different platy fish types? New colors and patterns are constantly being produced, but some of the most popular varieties include Mickey Mouse, sunburst, red wag, blue, bumblebee, and green lantern platies.

How big do platys get? Platies grow to around 2-3 inches (5-7 cm) in size, but dwarf platies (which have been selectively bred for their shorter body length) usually stay around 1 inch (2.5 cm).

What is the lifespan of a platy fish? Healthy platies can live up to 3-4 years when kept in optimal environments with clean water, low stress, and good nutrition.

How much do platy fish cost? Platies are relatively inexpensive and can be found at fish stores for $2 to $4 each, depending on the type. Try to get the healthiest fish that have bright eyes, full bellies, and active behavior. If you notice other sick fish in the same tank, it may be safer to visit another store to get your platies.

How Do You Set up a Platy Fish Tank? Platies can live in a 10- to 20-gallon aquarium or larger. Most livebearers prefer higher pH, but platies can tolerate a very wide range from 6.8-8.5 in our experience. They also enjoy harder water, so if your tap water is especially soft, consider adding more minerals using Seachem Equilibrium or Wonder Shell. We also like to keep our platies with live aquarium plants to help consume some of the organic waste produced by the fish.

Do platy fish need a heater? Most platies do well with temperatures from 70-82°F, but if your air conditioning is set on full blast, you may want to consider getting an aquarium heater. However, variatus platies are accustomed to living in cooler waters and do not require extra heating when kept at room temperature.

Do platies need an air pump? You can use almost any type of aquarium filter with your platies, including those that run on an air pump. Aquarium filters help keep the water clean of floating particles, process nitrogen waste in the water, and ensure your fish get enough oxygen. Read this article for more information on which filter is right for you

Can platys survive in a pond? Yes, we highly recommend variatus platies as an excellent fish to keep in an outdoor mini pond during the warmer summer season. Read our mini pond tutorial for more details on how to set one up.

How many platies should be kept together? A group of three to six platies is a good starting point. As with most livebearers, the males constantly want to mate, so try to keep at least two females for every one male to give the girls a break.

Can platy fish live alone? Yes. While platies do seem to enjoy the company of their own kind, they don't tend to school together in a tight group unless they think you're about to feed them. 

What fish can live with platies? These friendly livebearers can be kept with any similar-sized community fish. Some peaceful tank mates to consider include small tetras and rasboras, cory catfish, snails, bristlenose plecos, and rainbowfish.

Can platies live with betta fish? Most likely. In our experience, betta fish can usually live in a peaceful community tank with platies. Just make sure they are housed in a large enough aquarium with lots of plants or decorations so that the betta has enough territory to call his own.

How often should platys be fed? Once a day is fine for adults, whereas two to three small meals a day is preferred for growing juveniles. If you notice long strings of poop constantly dangling from your platies, you may be overfeeding your fish so consider decreasing their portion size.

How long can platies go without food? In the wild, food is not always available, so fish do not necessarily get to eat every day. If you are going on vacation for a week or less, your fish can easily survive without any food. However, if you will be away for two or more weeks, consider getting an automatic fish food feeder or finding a pet sitter to take care of your fish.

How Often Do Platy Fish Make Babies? Platies are livebearers, which means that they give birth to live young. Compared to fish babies that hatch from eggs, livebearer fry are usually bigger, faster, and have a much higher survival rate. In the right conditions, female platies can give birth to 20 to 50 babies per month.

Will platy fry survive in a community tank? Adults display no parental care toward their young and will happily eat them if given the chance. (In fact, one way to control their population is to allow the other adult fish to eat the fry so that only one or two from each batch will survive.) If you wish to increase their survival rate in a community tank, provide lots of decorations, rocks, wood, or live plants as cover for the fry to hide behind. Also, if you're using a hang-on-back or canister filter, make sure to cover the filter's intake tube with an appropriately sized pre-filter sponge so that they don’t accidentally get sucked up.

2. Danio fish

Danio Fish or Zebra danios are a favorite of freshwater fish hobbyists because of their ease of care. They are also prolific breeders and the easiest type of egglayers to breed. With their attractively striped, black and white zebra-patterned bodies, these fish are easy to recognize.

Zebrafish are very durable and can withstand an impressive range of water temperatures and conditions. They will generally do just fine without a water heater as they are comfortable at temperatures as low as 60 degrees Fahrenheit.

Origin and Distribution

Zebra danios were originally thought to have originated from a wider range that stretched from Myanmar in the east and Pakistan in the west; however, the current consensus is that this species originates from a much narrower range that is confined to parts of India and Bangladesh.

Part of this change in distribution is due to the identification of similar species that were once misidentified as Danio rerio. Damage to the environment that resulted in a reduction of habitable areas has also narrowed their natural range, even though wild zebra danios utilize a variety of habitats, ranging from fast-moving streams to slow-moving, nearly stagnant ponds.

Zebra danios available in the aquarium industry are now almost always captive-bred as zebras are easy and inexpensive to raise. While commercial breeding has provided a large and unlimited supply of this species, it has also resulted in a fish that is less robust than the original wild species. Many varieties of zebra danios are available now at your local aquarium store.

Colors and Markings

The zebra danio is easily recognized by its distinctive horizontal stripes. Blue-purple horizontal stripes run from gill to tail, setting off the slim, compressed, silver-gold body of this attractive fish.

Albino, golden, veil-tailed, and long-finned zebra danio varieties are available, as well as a popular leopard variety. The leopard strain is characterized by a sprinkling of black spots over the entire body. In the past, the leopard danio was considered a different species, but genetic studies have proven that it is merely a spotted variation of Danio rerio.

A brightly colored variety of zebra danio is now available called GloFish. These fish have had fluorescent pigment introduced into their DNA that makes them brightly colored. They still have dark stripes but the body color is now orange, green, blue, purple, or red.

Tankmates

The small size of the zebra danio, no more than two inches, makes them well suited to a community aquarium. Zebra danios are peaceful fish that get along with most tankmates, however, they will nip the fins of some species. Any fish with long-flowing fins, such as angelfish, bettas, and guppies, are potential targets of the active zebra danio. Good potential tankmates may include similar-sized danios, barbs, corydoras catfish, tetras, loaches, mollies, plays, and swordtails.

All varieties thrive in schools and should never be kept as singles. They do best when kept in a school of five or more of their own kind. Groups of this fish can be hierarchal, and a pecking order may emerge in the school, but there is no fighting. Select tankmates that are similar in temperament and that can keep up with the fast-paced behavior of this danio. Mellower fish that need a less hectic environment can become stressed in their presence.

Breeding the Zebra Danio

Zebra danios are ideal for beginners as they are prolific breeders, and interestingly, females can spawn every two to three days after reaching sexual maturity at about four months. The best way to obtain a mating pair is to start with a school of a half dozen or more young zebras and allow and watch for the females to develop rounded bellies. When the females are full of eggs, separate one or two females and two to four males into a separate breeding tank.

Set up a separate breeding tank with shallow water, approximately 6 inches deep. Furnish the tank with fine-leafed plants. The bottom needs to be covered with a coarse substrate such as marbles or large gravel/pebbles so that the eggs will fall between the substrate pieces and will be protected from the adult fish, which will readily eat their own eggs once they lay them. A wide-mesh breeding net holding the adults can also be suspended in the tank. The mesh needs to be large enough for the eggs to fall through the netting, without letting the parents out.

When preparing to breed them, providing a water change can help induce spawning. Spawning requires temperatures of up to 78 to 80 degrees Fahrenheit and can be triggered by raising the water a few degrees near dawn—when spawning normally occurs. About 300 to 500 eggs will be scattered across the bottom and on the plants. Remove breeders after spawning, as they will also consume the young as they hatch.

The fry will hatch in about two days, depending on the water temperature. The fry are very tiny and can easily be lost when changing water, so take care when maintaining the nursery tank. A sponge filter is best to use in the breeding/nursery tank so the babies do not get sucked into the filter. Feed the young commercially prepared fry food or finely crushed flake foods. You can also add a powdered egg to fry food to promote growth. Be sure not to overfeed as uneaten food will foul the water quickly.

3. Angelfish

What are Angelfish? Angelfish are a species of cichlid fish found throughout the Amazon River system and in several South American countries. The unique appearance of the angelfish comes from its long fins that flow gracefully through the water as it swims, and varieties are typically identified based on different types of stripes or markings.

There can be some confusion about the term “angelfish” since the saltwater aquarium hobby has marine angelfish, so we are specifically referring to the angelfish cichlids of the Pterophyllum genus that have long, wing-like fins and come from freshwater rivers in South America. The three known species of angelfish include P. altum (the largest species), P. leopoldi (the rarest species to find in fish stores), and P. scalare (the most available species found in pet stores).

What are the different angelfish types and colors? New colors and patterns of angelfish are constantly being developed, but some of the most well-known varieties include silver (or wild type), veil, koi, zebra, marble, albino, leopard, and platinum.

How big do angelfish get? These fish get to the size of a small saucer, so be prepared to give them plenty of space. The common P. scalare angelfish has a body length of up to 6 inches (15 cm) and a height (including their fins) of 8 inches (20 cm). Altum angelfish (P. altum) can grow up to 7 inches (18 cm) long and 10-13 inches (25-33 cm) high.

How long do angelfish live? If given a clean environment with minimal stress and high-quality foods, angelfish can live up to 8 to 12 years long.

How much do angelfish cost? Depending on the size of the fish and rareness of its color variety, the price can range between $5 to $20 and upwards.

Are angelfish aggressive? Many pet stores label angelfish as “semi-aggressive” because they are known to chase each other in the aquarium. This territorial behavior is primarily due to breeding. Males spar with one another to win their favorite female, and parents often defend their eggs and fry from being eaten by other fish. However, compared to other cichlids, angelfish are relatively peaceful and can be kept in a community aquarium with the right set of tank mates (see below for specifics).

How Do You Pick Healthy Angelfish? When buying angelfish at a store, look for ones that are the size of a U.S. nickel, quarter, or half-dollar coin (0.8-1.2 inches or 2-3 cm). Half the fun of fish keeping is watching your fish grow from a young age to full adulthood. While angelfish are a relatively slender fish, don’t pick ones that are overly thin. Look for young, strong fish with a thicker head and meaty body. If possible, ask the store to feed them so you can select the most aggressive eaters. Also, avoid any fish with cloudy or damaged eyes. Bring home the healthiest ones possible for the best chance of success.

How Do You Set up an Angelfish Aquarium? Angelfish can be kept in a wide variety of setups – such as bare tanks, community tanks, and planted tanks. Try adding a few beginner-friendly aquatic plants to help consume toxic waste compounds and add a beautiful slice of nature to your aquarium. For example, java fern provides tall, textured leaves for your angelfish to swim around, and it only needs some low light and a few squirts of Easy Green all-in-one fertilizer to stay alive.

As for water parameters, angelfish tend to prefer warmer temperatures between 78-86°F. (Dean keeps his tanks around 82°F for breeding and raising fry.) They are not very picky about pH and can live in a wide range from 6.0 to 8.0 (although closer to the middle is always better). Water hardness may matter a little more since many captive-bred angelfish in the United States come from Florida, which is known for having hard water or high GH levels. Angelfish can usually adapt to soft water with no problems, but you can also look for a local breeder who has similar water parameters as your own.

What size tank do angelfish need? The aquarium size depends on how many fish you plan to have. For a 29-gallon community tank, keep no more than four adult angelfish with other tank mates. For a 55-gallon tank, start with five or six juvenile angelfish and be prepared to remove some in the future if they get too territorial. If the angelfish are kept in overcrowded conditions, make sure to increase the frequency of your water changes to keep the water quality high.

Can angelfish be kept alone? In our experience, keeping a single angelfish does not seem to adversely affect their well-being. While they do shoal or swim together in the wild, having just one as the centerpiece fish in your aquarium seems to make them much more easygoing and docile overall.

What fish can be kept with angelfish? Because of their long, gorgeous fins, stay away from any fin nippers or fast-swimming fish that will outcompete your angelfish during mealtimes. Also, given how large they can grow, don’t buy any nano fish or small creatures that can be eaten by your angelfish (like microrasboras or dwarf shrimp). We’ve had good luck with black skirt tetras, adult cardinal tetras, and cory catfish.

Guppies are on the “maybe” list for tank mates because of their smaller size, so you may want to try a larger type of livebearer if you’re worried about them. (Certainly, the angelfish will help keep any livebearer population under control by going after their fry.) Betta fish are another species in the “maybe” category. The angelfish may try to attack the betta fish, so consider choosing a giant betta or regular betta with shorter fins to increase their swimming speed.

What Do Angelfish Need to Breed? Unless you’re an experienced angelfish keeper, it can be hard to spot the differences between males and females. Therefore, the easiest method of getting a breeding couple is to buy at least 6 juvenile angelfish, raise them to adulthood, and let them pair off naturally. Pick the best-looking pair and move them to their own aquarium for spawning. (A 20-gallon high breeding tank is a good size, since it has plenty of height for their fins to fully extend.) Once they breed, you can easily determine the sex since the female is the one laying the eggs. Afterwards, you can mix up the pairs if you want to match up two specific fish with desirable qualities.

How often do angelfish lay eggs? Angelfish readily breed and can lay hundreds of eggs every one to two weeks if the eggs are removed or eaten. (The first couple of spawns often fail because the new parents can end up consuming them.) However, with the right conditions and a little patience, your angelfish can successfully raise their own offspring. The eggs are typically laid on vertical surfaces like a stiff leaf, filter pipe, or a section of aquarium wall. Depending on the tank temperature, the eggs will hatch in two to three days, and the parents may move the newly hatched wigglers (fry that cannot swim freely yet) around the aquarium with their mouths. In another three to four days, the fry become free-swimming, and the parents will protectively keep their cloud of babies between them. At this time, start off the fry with tiny, nutritious foods like baby brine shrimp and Hikari First Bites powder.

4. Betta fish

Origin and Distribution

Bettas originate in the shallow waters of Thailand (formerly called Siam, hence their name), Indonesia, Malaysia, Vietnam, and parts of China. These areas are home to rice paddies, ponds, slow-moving streams, and swamps, all of which are home to bettas. Today, bettas have been introduced into many other locations, giving rise to non-native populations in several countries.

The common name, Siamese fighting fish, was coined due to the practice of organized fights between males, much like cockfights. These matches continue to this day, driven by the income from betting. In some locations males are bred specifically for aggression, to ensure better fights. However, having male bettas fighting each other is considered cruel and should not be done.

Colors and Markings

The brilliant coloration and long flowing fins of the male betta make it one of the most well known of aquarium fish. Females are usually not as highly colored and have much shorter fins. In nature, this species is not usually brightly colored.

However, captive breeding programs have resulted in a wide variety of colors, including white, yellow, orange, red, pink, blue, green, turquoise, brown, and black. A myriad of combinations can be seen, from solid colors to those with different fin and body colors, to patterned colors. Fin types have also changed due to selective breeding. Veil tails have been joined by crown tails, deltas, fans, half moons, lyre, and split tails, to name a few.

Both sexes have a torpedo-shaped body and an upturned mouth geared for eating at the surface. Mature adults reach a size of two to three inches, with females being slightly smaller than the males. A unique feature of this species is the presence of a labyrinth organ that allows them to take oxygen from the atmosphere instead of from water, thus allowing them to survive in low-oxygen pools.

Tankmates

Males cannot be kept together unless there are separators in the tank. Multiple females can generally be kept together without problems. Several females, or one male, can be kept with other peaceful fish species, as long as they are small and are not fin-nipping types, such as tiger barbs.

Betta Habitat and Care

Bettas are one of the most recognized, most colorful, and often most controversial fish in the freshwater aquarium hobby. Debates rage about the appropriateness of keeping them in small bowls. To fully understand their needs, it is important to become familiar with their native habitat, where they live in large rice paddies, shallow ponds, and even in very slow-moving streams. Although many fish keepers are aware that bettas come from shallow waters, the warmer water temperature is often overlooked.

The home countries of the betta are tropical, which means the water temperature is quite warm, often into the 80s. Maintaining proper water temperature is perhaps the biggest argument against keeping a betta in a bowl, which cannot readily be heat-controlled. Really, the best option is to house them in a betta fish tank, with an aquarium heater and water filter.

Since it's so important for bettas to live in warm water, you'll want to get an aquarium water heater. Consider the size of your tank when looking for a heater; the standard rule is the heater should have 5 Watts of power per gallon of water. You can get a floating thermometer or a digital one that attaches to the aquarium glass. Place the thermometer where you can easily read the water temperature. You'll want to perform a partial water change at least once a week.

Even though bettas do well in water that is low in dissolved oxygen, that does not mean they require less oxygen than other fish. Bettas have a special respiratory organ (called the labyrinth organ) that allows them to breathe air directly from the surface. In fact, they inherently must do so. In experiments where the labyrinth organ was removed, the fish died from suffocation even though the water was saturated with oxygen. For this reason, bettas must have access to the water surface to breathe air directly from the atmosphere.

Optimally, the water for keeping bettas healthy should be soft and warm, with a neutral to slightly acidic pH. Water movement should be kept to a minimum, which means that power filters and powerheads are not suitable. Bettas may be kept in a community tank as long as the water conditions are met, and if no aggressive or fin-nipping fish are present. However, only one male may be kept in each aquarium, unless they are separated by a barrier. The use of plastic boxes that hang inside the aquarium is a suitable option for keeping more than one betta in a tank, or for keeping them in a tank with fish that might nip their fins. Females will generally not fight with each other and may be kept together in the same open space. Female bettas can also be kept with other non-aggressive fish species.

5. Tetra fish

Origin and Distribution

Tetras are schooling fish from the family Characidae. They are calm, colorful and mostly peaceful, making them ideal for both beginner and advanced hobbyists. Popular beginner tetras include red eye, black skirt, serpae and bloodfins, but neons, black neons, glowlights and lemon tetras can be good choices as well. Others, like cardinals, emperors and penguin tetras are more challenging to keep and do best in well-established aquariums with softer, more acidic water. Selectively bred color variants and long-finned strains of certain tetras are also available.

Natural Habitat for Tetras

Tetras are found in the Americas and Africa, with the vast majority coming from the Amazon Basin and other river systems of South America. They mostly inhabit rivers and streams, although one unique species, the blind cave tetra, was discovered in a cave system in Mexico!

Tetras Water Requirements

While most tetras are found in soft, acidic water in the wild, the majority of aquarium species sold today are raised commercially in water that often has a higher pH and alkalinity than their native environments. For most tetras, pH should be between 6.8 and 7.8, alkalinity between 3° and 8° dkH (50 ppm to 140 ppm) and temperature between 75° and 80° F. If the aquarium is kept in rooms below 75°, use an Aqueon Aquarium Heater to maintain the correct temperature. Exceptions like the Buenos Aires tetra do better in cooler water. Maintain good filtration and change 10% of the water every week or 25% every 2 weeks using an Aqueon Aquarium Water Changer or Siphon Vacuum Gravel Cleaner. Do not forget to treat tap water with Aqueon Water Conditioner before refilling your tank!

Housing Requirements for Tetras

Most tetras can be kept in aquariums of 10 to 20 gallons, but larger tanks are easier to take care of and give them more room to swim. They do best in schools of 6 or more and will be less stressed and show their best colors in a well-decorated aquarium. Dark substrates and decorations will help accent the bright colors of your tetras. Keep a secure lid on the aquarium to prevent them from jumping out if they feel scared or threatened. Provide mild but steady current.

Tetras Behavior/Compatibility

Most tetras are peaceful and get along well with similarly sized community fish, but there are a few exceptions. Serpae tetras, for example, can sometimes be nippy, especially when kept in insufficient numbers. Others, like Buenos Aires tetras get quite large and are very active, which may intimidate smaller, more timid fish. Good tank mates for tetras include other tetra species, rasboras, small danios, peaceful barbs, appropriately sized rainbowfish and livebearers. Always consult an aquarium expert before buying any new fish for your aquarium.

What Do Tetras Eat?

Most tetras are omnivorous and will thrive on Aqueon Tropical Flakes, Color Flakes, Tropical Granules and Shrimp Pellets. Frozen and live foods can also be fed as treats or to help induce spawning. For best results, rotate their diet daily and feed only what they can consume in under 2 minutes, once or twice a day.

Tetras Breeding Level - Difficult

Tetras can be bred in captivity, but it can be difficult to create the correct environment to propagate and raise fry. Tetras are egg layers, but extra effort is required to separate the adults from the eggs after spawning as many tetras will eat their own eggs. Tetras tend to spawn in groups. Males typically entice females into thick plant growth, where eggs are deposited and fertilized and hatch in a few days.

6. Guppy fish

Guppies have been a staple of the aquarium hobby for generations. Originating in tropical pools in South America and the Caribbean Islands, these fish are now available in a wide variety of colors that have been produced by selective breeding at fish farms. Many guppy keepers may start out with only one or two fish, but being live-bearers with long-term sperm storage, you may be in for a full tank before long.

Origin and Distribution

The guppy has been captive bred for over 100 years, but originally came from South America. They are named for Robert John Lechmere Guppy who collected these fish on the island of Trinidad in 1866. They are native to freshwater streams in the north of South America, including Surinam, Guyana, and Venezuela, and the Caribbean islands, including Barbados and Trinidad and Tobago. Now, they have been introduced to every continent but Antarctica, and can be found in many warm waterways around the world

Colors and Markings

Whatever color combination you can dream of, there is probably a perfect guppy for you. Males have more vibrant colors than females, such as white, red, yellow, orange, green, blue, purple, and black, and have longer caudal and dorsal fins. Tail fins may have a marbled or striped appearance, or the fish may be all one or two colors, such as various shades of blue, black, orange, green, yellow, red, purple, and white. Depending on the variety, some guppies have short, rounded tails, some "V"-shaped, and others can have an elongated tail half the length of their body.

Many websites and some pet stores will offer "select" or "unique" varieties found nowhere else. Many times, these strains are the result of serious inbreeding that produces fish with compromised immune function and a shorter life span. Try to stick to the mainstream varieties with well-established lineages. If you end up breeding two different strains, you may be surprised by how the color variations mix.

Tankmates

Guppies are peaceful, easygoing community fish that play well with a mix of other non-aggressive fish species. You may want to keep them with similar, live-bearing fish, such as platys or mollies. Other good tankmates include small fish, such as neon tetras or zebrafish. Keep in mind that any fry spawned from an active guppy female may be dinner for other fish in the tank, so having smaller tankmates will ensure more fry survive.

Many guppy keepers often opt for a guppy-only aquarium. You are welcome to mix different varieties of guppy in the same tank. The number of guppies you can keep in one tank will depend on the size of the tank—a general guideline is 1 gallon of water for every 1 inch of fish. For example, because guppies average around 2 inches in length, a 10-gallon tank may only hold five guppies comfortably, while a 30-gallon tank may hold 15 guppies. Generally, it’s also best to have two or three females for every one male in the tank.

Guppy Habitat and Care
Guppies are great beginner fish. They are low maintenance and can tolerate some beginner mistakes. A bigger tank size is recommended since guppies are very active fish. They thrive in an aquarium with plants and soft décor items.

In order to keep your population from exploding, it is strongly recommended that you separate males and females in different tanks. Guppy females can store sperm for multiple spawns, even after separation from males, so once a female has been with a male, she may have multiple batches of babies. Tank dividers are okay as a temporary solution, but many of these flimsy, plastic dividers are usually not enough to keep fish separated. Two separate tanks will keep unwanted spawning to zero.

Heater
As a general rule, you need a heater to keep your guppies healthy. They prefer water temperatures in the 70s, and few homes are warm enough to provide that without an immersible heater in the tank. Monitor water temperature daily and adjust the heater as needed to keep your fish comfortable and healthy.

Filtration
Your aquarium definitely needs a filter to remove impurities and harmful chemicals from the tank water. Without a filter, aquarium water tends to quickly become filled with pollutants from uneaten food and fish waste, and your fish can become ill or even die from this harmful water. There are many types of aquarium filters available to suit any budget, so talk to the fish expert at your local aquarium shop or pet store if you are uncertain as to which filter is best for your tank.

Guppy Diet and Feeding
Guppies are omnivores and do well on a variety of commercially available feeds. Even though guppies are small in size, pelleted diets called micro pellets are the best choice since they hold onto their nutrition longer than flakes. You are welcome to add supplements, such as frozen fish foods, but no more than once or twice a week. The complete pelleted diet is best for most pet fish species.

Depending on your aquarium's temperature and the other tank inhabitants, you may feed your fish once or twice a day. Always start with a little bit of food, and when it has all been consumed, add a little more. Repeat for a few minutes and use this time to check all of your fish. Feeding time is a great time to see if any of your fish are acting odd or sick.

Gender Differences
There are a few gender differences you will need to identify to keep your male and female populations separate. Males tend to be smaller and more vibrantly colored. Females tend to have a brown coloration and are larger and rounder. Also, as male guppies grow, their body will develop coloration that does not occur on the female's body.

On the underside of the fish, the anal fin of the male is long and thin and tapers to a point. The anal fin on the female guppy is larger and triangular or fan in shape.

Guppies are sexually mature in about two to three months, and you should be able to identify the differences between genders by 1 month of age, if you wish to separate them. Female guppies first produce offspring at 10–20 weeks of age, and they continue to reproduce until 20–34 months of age.

Breeding the Guppy
Many beginner hobbyists will start with only one female guppy and suddenly have a swarm. Since female guppies can store sperm, it only takes one insemination by a male for a few spawns to be born. In order to prevent your aquarium from maxing out its stocking capacity, it is always best to separate male and female guppies.

Guppies are live-bearers, so the female will give birth to 10–50 wiggling fry per spawning. Many times, the newly born fry will be eaten by other fish in the aquarium, so if you want to save any fish, keep them in a separate tank or breeding box. Heavily planted aquariums will also give the babies places to hide and survive.

After breeding together many generations of the same population, you may notice an increased number of fish with congenital abnormalities, such as crooked spines or shortened lifespans.

7. Tiger Barb fish

The very popular tiger barb is an easy fish to care for and can be fun to watch as it swims at high speed in schools of six or more. It is not, however, an ideal fish for a community tank as it can be mildly aggressive and nip any fish with flowing fins. When well cared for, tiger barbs have a lifespan of five to seven years.

Origin and Distribution

The tiger barb is native to Borneo and Malaysia, including Sarawak and Kalimantan. They can also be found on the island of Sumatra and in Thailand and Cambodia. Non-native tiger barbs have been introduced in Singapore, Australia, the United States, and Colombia.

In their native habitat, these fish inhabit quiet, tree-lined rivers and tributaries filled with sand, rocks, and thick vegetation where they can find insects, algae, invertebrates, and detritus from plants. They prefer clear, highly-oxygenated water.

Colors and Markings

Four tiger-like black vertical bands on an orange-yellow body make it obvious where this member of the barb family got its common name. Red-edged fins and a red face add even more color to the popular tiger barb. In recent years, selective breeding has created several color variations that include green, black, red, and albino. A genetically modified glow version of the tiger barb occurs in many colors.

Tankmates

Reaching an adult size of 2 1/2 to 3 inches, they are large enough to avoid being eaten by large fish, yet small enough to keep a school of them in a modest-sized aquarium. For a striking display, set up a species-specific tank with a half dozen of each color variation of tiger barb, complemented by live plants.

Provided there is considerable space, one of the best tankmates for the tiger barb is the similar looking clown loach; it will even school with the tiger barbs and act as they do. Alternatively, pair the tiger barb with fast-moving tankmates such as danios, platys, loaches, or catfish.

Tiger Barb Habitat and Care

Tigers barbs tolerate a wide range of water conditions, but do best in soft, slightly acidic water. The ideal tank should have a large open area for swimming with an abundance of live or artificial plants around the periphery of the tank. Temperature is not critical, and this fish can even be kept in an unheated tank. Provide good lighting and a fine substrate to complete the setup.

Tiger Barb Diet and Feeding

Accepting of virtually any food, tiger barbs should be given a variety of foods to maintain a healthy immune system. Include quality pelleted or flake food, as well as live and frozen foods such as brine shrimp, bloodworms, and beef heart. They will quickly gobble up small aquatic invertebrates and even cooked vegetables.

Breeding the Tiger Fish

As egg-scatterers that provide no parental care, tiger barbs will eat their own eggs if they have the opportunity. Therefore, it is advisable to set up a separate breeding tank that can double as a grow-out tank for the fry. To acquire a breeding pair, keep at least a half dozen barbs and allow them to pair off. Condition the breeders with live foods, and once a pair has been established, move them to the separate breeding tank.

The breeding tank should have soft, acidic water, fine-leaved plants, and a bare bottom. Some breeders use marbles or a spawning grid on the bottom, which allows the eggs to drop safely out of the parents' grasp. Keep in mind that if the bottom is bare, it is particularly critical to observe closely, removing the parents immediately after spawning and before they can consume their eggs.

Spawning will usually take place in the morning. If the breeding pair does not spawn within a day or two, a partial water change with water that is a degree or two warmer than the tank water will usually trigger spawning. If more intervention is still necessary, lower the tank water level by an inch, then use a watering can sprinkler to add the colder make-up water to the tank. The sprinkling vibrations mimic the conditions of the natural rainy season, sending more of the appropriate hormonal cues that it is time to spawn.

The female will lay about 200 transparent- to yellowish-colored eggs, which the male will immediately fertilize. As soon as the eggs have been fertilized, the breeding pair should be removed. The eggs will hatch in approximately 36 hours, and the fry will be free-swimming after five days. Feed the fry newly hatched brine shrimp until they are large enough to accept finely crushed flake food or commercial powdered fry food. 

8. Cory Catfish 

Corydoras catfish, or cory catfish, are beloved by all who have owned them. These peaceful fish are hardy, attractive, and lively. They can even help you keep your tank clean. Virtually all cory species should be kept in schools; stories of single corys pining away from loneliness are not uncommon. Corys should be kept only with small- to medium-sized peaceful fish.

What are Corydoras?

This genus of South American catfish includes more than 160 species, with several hundred more that are waiting to be classified. Ranging from 1 to 3 inches long in the aquarium hobby, they’re named after the bony plates of armor on their body. For protection against predators, these little catfish also have sharp spines in their fins that can sometimes produce a mild venom when stressed (in other words, don’t try to catch them with your bare hands).

Depending on the species, most cory catfish enjoy temperatures between 72 and 82°F. For example, peppered cory catfish (Corydoras paleatus) and julii cory catfish (Corydoras julii) are found on the cooler end of the spectrum, whereas sterbai cory catfish (Corydoras sterbai) can live in higher temperatures. They also prefer pH levels ranging from 6.5 to 7.8.

In the wild, corydoras have been observed in large groups numbering from 20 to hundreds of the same species. They are most active in the daytime, with peak activity occurring at dawn and dusk. The most popular varieties in the pet trade include the bronze cory and albino cory (Corydoras aeneus), panda cory (Corydoras panda), emerald green cory (Corydoras splendens), and pygmy cory (Corydoras pygmaeus).

What Size Tank Do Cory Catfish Need?

For dwarf species, a 10-gallon aquarium may be suitable, but we recommend 20 gallons or more for most other varieties. As a relatively small fish, they crave safety in numbers, so a group of six corydoras or more (all of the same species) is highly suggested. These peaceful bottom dwellers can be kept with pretty much any community fish that won’t eat or attack them. (For instance, don’t keep corydoras with goldfish, which get rather large and will inhale anything that fits in their mouth.)

If you’re looking for fish stocking ideas, a 20-gallon aquarium could house a school of cory catfish swimming at the bottom, a school of small tetras swimming in the middle layer, and a centerpiece fish like a honey gourami. Add some lush aquarium plants and you’ve got a miniature ecosystem in your living room!

Do Cory Catfish Need Sand Substrate?

Corydoras have wispy barbels or whiskers to help them find food, so smooth sand or gravel is preferred. (That being said, our CEO Cory McElroy visited their natural habitat in the Amazon and found the substrate to be quite sharp, as seen in this video.) In general, it helps to feed larger foods like worms and Repashy gel food that can sit on top of the substrate and not get trapped in between cracks where the corys can’t reach them.

In the wild, corydoras can be found on sharp substrate, so if their barbels start to erode, it may be caused by other factors like poor water quality.

What Should I Feed My Cory Catfish?

Speaking of diet, corydoras are not picky eaters and will eat anything small or soft enough to fit in their mouths. They love worms of all types, so try live blackworms, frozen bloodworms, and Hikari Vibra Bites (tiny food sticks that look like bloodworms). They also enjoy Repashy gel foods, sinking wafers, and other sinking community foods.

They are not primarily algae eaters, so you will need to specifically feed them to make sure they get enough nutrition. If housed with more aggressive eaters, it can be easy for cory catfish to get outcompeted during feeding times, causing them to waste away.

Can You Breed Cory Catfish in Aquariums?
Yes, very easily! Many fish keepers find that their corydoras breed randomly all the time without any special effort. Males have a smaller and thinner profile, whereas females are rounder and larger to hold all the eggs. Condition them (or prepare them for breeding) by feeding lots of nutritious foods, such as live blackworms and frozen bloodworms. You can also induce spawning by introducing cooler than normal water (by a few degrees) during water changes to imitate the rainy season. Soon enough, you’ll find sticky round eggs all over your tank walls and decor.

If you want to breed the catfish in the same tank they live in, it helps to provide lots of cover – such as a dense mass of java fern or guppy grass – and remove other species of fish. All fish (including the parents themselves) will happily eat the eggs, given the chance. For a higher survival rate, you can remove the eggs (with your fingers or a credit card) into a separate aquarium to raise the fry. Feed the baby catfish plenty of live baby brine shrimp and powdered fry food, keep on top of the water changes, and enjoy a whole new generation of corydoras.

9. Goldfish

Despite popular opinion, goldfish (Carassius auratus) are not "maintenance-free" or "trial" pets. They require and deserve just as much care as any other pet. Goldfish are hardy species and good at tolerating many beginner's mistakes, but you will need to put in some effort to ensure their health and survival. They should not be kept in a fish bowl, but require an aquarium with proper water aeration and filtration.

Types of Goldfish

There are many different varieties of goldfish. They are commonly divided into standard (long-body) and fancy (round body) varieties. The common Comet Goldfish is the most common pet fish species. Although they are often sold in the pets stores very small, these fish can grow up to 14 to 16 inches long and may require up to 100 gallons at their full size. Shubunkin and Sarasa goldfish varieties have the same body type, but are often more colorful fish, with combinations of red, white, black and yellow colors.

Fancy varieties of goldfish are numerous and have many anatomical adaptations. These breeds include the Oranda, Ranchu, Telescope, Fantail, Celestial, Moor, and other varieties. They have egg-shaped or rounded bodies. Given their body structure, they usually do not grow as large as long-body goldfish and may have some structural issues. These fish are more prone to buoyancy issues, spinal disease, and traumatic injury due to their protruding eyes and delicate fins. The Oranda goldfish has a fleshy growth on its head, called a wen, that may even need trimming if it overgrows the fish’s eyes or face.

Environmental Requirements

No matter what variety of goldfish you keep, maintaining a proper aquatic environment is critical. You will need at least 20 gallons of water per goldfish, and expect your long-body goldfish to outgrow this within the first 5 to 10 years. Comet goldfish can easily live into their 20s and some have lived over 40 years, with the fancy varieties usually surviving into their mid-teens.

Most goldfish are very tolerant of beginner water quality mistakes. They are very hardy species and can tolerate moderate levels of ammonia, nitrite, and nitrate in circulating tanks. Once your aquarium nitrogen cycle has been established, it is recommended to keep your nitrate less than 20 mg/L, and the ammonia and nitrite at zero. In densely packed tanks, this may be hard to maintain without frequent water changes. Goldfish are notorious for constantly eating and creating a lot of waste—hence the spatial needs. They can also tolerate a wide range of pH, provided your kH (Carbonate Hardness = alkalinity) is high enough to stabilize the pH levels.

Goldfish are natural foragers and may spend most of their time digging around in the substrate of their aquarium or pond looking for food. They like to suck every last morsel out of their meals and will often pick up small rocks in their mouth to clean off food particles. These have a very low chance of getting stuck in their mouth, so don't worry about your fish picking them up.

Housing Goldfish Outdoors

In addition to indoor aquariums, goldfish can also be kept in outdoor ponds. Their hardiness makes it easy for them to stand up against temperature changes throughout the days and seasons. Provided your pond is large enough and properly built, your goldfish may enjoy spending all their time outside, or, in colder climates, splitting their time between outdoors and indoors. Outdoor ponds should have at least 30 gallons of water per goldfish and should have aeration and a filtration system. The water depth should be a minimum of 3-4 feet, deeper in colder climates.

It is not recommended to put fancy goldfish varieties in large, outdoor ponds. They are not well setup to swim large distances and the increased depth can put additional pressure on their swim bladder, augmenting buoyancy disorders. Due to their poorer swimming ability, they cannot compete with comet goldfish or koi for food, and they are more prone to predator attacks.

How Much and How Often to Feed Goldfish

Goldfish are often compared to Golden Retrievers for their similar appetites and ability to gorge themselves. They love to eat and, depending on the temperature of their water, may seem almost insatiable. No matter what fish species you keep, since they are ectotherms, the warmer the water, the hungrier your fish will be. With water temperatures below 70F (21C), feed your goldfish at least once a day. Above this, you will need to feed your goldfish twice a day. Give the fish as much food as they will eat in 3-5 minutes.

Look for a goldfish diet around 30-35% protein and 5-7% fat. For reproductively active, breeding fish or juveniles, you will need to select a diet higher in protein and fat. There are many commercial diets available within this range for goldfish. Weekly protein-rich treats, such as bloodworms or brine shrimp, are appropriate only in warmer water. Shelled green peas, not actually a cure for "constipation," are a better treat to feed more often.

Fancy goldfish and their buoyancy disorders can be related to diet. Being voracious surface eaters, a goldfish may suck in too much air during feeding and become temporarily positively buoyant. Switching to a sinking diet, or vice versa for negatively buoyant fish, will take advantage of their physostomous anatomy, where the gas bladder is connected to their digestive tract at the pharynx, and correct the buoyancy disorder without veterinary intervention.

Goldfish Maintenance Requirements

Although they are tolerant of beginner's mistakes, goldfish aquariums and ponds require regular maintenance. You will need to properly clean your filters on a weekly basis, but do not replace them all at once, as you may lose the necessary bacteria in them that break down fish wastes. Use a gravel siphon at least once a week to remove the debris and detritus from your substrate and top off your tank with conditioned fresh water.

As with all fish systems, it is highly recommended to purchase a liquid-based water quality test kit to maintain good water chemistry. Check it before and after your water changes to keep a close eye on the water quality in your goldfish aquarium.

10. Rainbow Fish

Rainbowfish are common freshwater community fish, but are you aware of how many species are out there? All members of the Melanotaeniidae family, rainbowfish are a wonderfully diverse group of fishes that are native to the islands of Australia, New Guinea, Indonesia, Sulawesi, and Madagascar.

Almost all rainbowfish species are community fish that get along with other non-aggressive freshwater fish species in an aquarium. Keep in mind, fish from different parts of the world will often have different water quality requirements, so not all species need the same water parameters.

There are many species on this list that are endangered or threatened in the wild. Here are some of the most colorful ones available from fish retailers.

Species Characteristics

Rainbowfish are classified by their elongated premaxillary teeth. They live in freshwater, including rivers, lakes, and swamps. They prefer to live in planted areas and reproduce by laying eggs. Most rainbowfish species prefer schooling together in a small group. There are various sizes and body shapes in rainbowfish.

How to Care for Rainbowfish

Whenever you are looking to add fish to your aquarium, ensure that your water quality parameters are correct before you mix different species. Trying to hit a "sweet spot" to accommodate a variety of water quality requirements may not end well. It is best to pick a mix of species that have compatible water requirements rather than mixing by appearance.

In a home aquarium, rainbowfish need well-oxygenated water with a pH level of 6.8 to 7.2, and optimal temperatures varying between 72 to 82 F (22 to 28 C). Provide plenty of aquatic plants to give them hiding places. If properly cared for, rainbowfish can live for five years in aquariums.

What Do Rainbowfish Eat?

Rainbowfish are omnivores, so they eat animals and plants. You can feed them a variety of fish foods and treats that can be purchased at pet stores, such as pellets and flakes as well as frozen, freeze-dried, and live foods.

How Many Rainbowfish Should Be Kept Together?

Most rainbowfishes like to be in a small school, so plan on having at least five to six individuals for the larger species and eight to 10 individuals for the smaller species. Ensure that your aquarium will have enough space for all your fish.

Rainbowfish are generally peaceful community fish, so they can easily be mixed with other tropical community fish, such as tetras, guppies, mollies, and danios—again, provided their water quality requirements are compatible.

Always thoroughly vet any potential vendor to ensure you are buying captive bred fish and are not taking any endangered fish from the wild. Many rainbowfish species are threatened or endangered and need to be purchased from a reliable vendor that sells commercially farmed fish.

11. Plecostomus Fish

Plecostomus Fish consisting of more than 150 species, are catfish who have sucker-shaped mouths and bony plates and spines over their bodies instead of scales to protect them. They can raise and lower their spines and plates when threatened by a predator. Plecostomus means “folded mouth” in Latin. These fish are well-known algae eaters who originated in the rivers of the Amazon jungle in South America. In nature, many live in fast-moving rivers and streams where they use their suckermouths to attach to rocks and wood to help prevent them from being swept away by water currents. Some pleco species have adaptations in their gastrointestinal tracts that enable them to breathe air and extract oxygen from it within their intestines. Plecos are often called “janitor fish” because they are scavengers and will eat and clean up almost anything. They are recommended for beginning aquarists.

The Armored Suckermouths

Plecostomus, or "plecos" as they are often called, belong to the Family Loricariidae, which is the largest family of catfish in the world. They are characterized by heavy armored plates on their bodies and sucker-shaped mouths. Scientists use a system of "L" or "LDA" numbers to identify plecostomus species, and at present, there are over 500 numbers with more being added each year. Some species, like the L046 Zebra and L177 Gold Nugget plecos, are brilliantly colored and command high prices in stores. Many plecostomus can breathe air due to modifications in their digestive tracts. For care and maintenance purposes, Farlowella and Otocinclus catfish can be included in this group.

Natural Habitat for a Plecostomus

Most Plecostomus species are native to South America, although a few can be found in Panama and Costa Rica. They occupy a wide range of habitats, although a number of species have very limited ranges and are only found in certain parts of specific rivers. Many plecos live in fast-moving shallow streams and rivers, while others inhabit acidic black water, and still others favor quiet, brackish estuaries. In high flow areas, they use their suckermouths to attach themselves to rocks and submerged trees to keep from being swept downstream.

Plecostomus Water Requirements

Loricariid catfish are typically found in soft water with a low pH in the wild, however, many species sold today are commercially raised and tolerate a much wider range of water chemistry. A pH between 7.0 and 8.0, alkalinity between 3° and 10° dKH (54 ppm to 180 ppm) and temperature between 74° and 80° F will suffice for most captive bred species. If the aquarium is kept in a room below 74°, use an Aqueon Aquarium Heater to maintain the proper temperature. Wild caught fish may require a temperature in the mid to upper 80's, pH of 5.5 to 7.0, and alkalinity below 3° dKH (54 ppm), so it is best to research fish you are unfamiliar with before purchasing. Maintain good filtration and do a 10% water exchange every week or 25% every 2 weeks using an Aqueon Aquarium Water Changer or Siphon Vacuum Gravel Cleaner. Do not forget to treat tap water with Aqueon Water Conditioner before refilling your aquarium!

Housing Requirements for Plecostomus

With so many species of suckermouth catfish to choose from, no matter what size aquarium or type of fish you own, there is one just right for you. For example, the common pleco, Hypostomus plecostomus, can grow to over 12" and will eventually need an aquarium of at least 75 gallons, while Otocinclus will be perfectly content in a 10-gallon tank. Plecostomus tend to be secretive, so caves, hollow logs and other size-appropriate hiding places should be available in the aquarium. Moderate to good circulation should be provided to simulate the fast-moving rivers many species inhabit in the wild. Decorate the tank with driftwood for refuge as well as a source of food.

Plecostomus Behavior/Compatibility

Many suckermouth catfish are nocturnal and spend a good portion of the day hiding in a crevice or under an overhang. However, some will adapt to aquarium life and be more sociable during the day, especially at feeding time. Loricariids are compatible with most aquarium fish, although tank mates should be roughly the same size as they are. Large predatory fish may try to eat smaller pleco's or Otocinclus, resulting in the catfish becoming lodged in the bigger fish's throat. On the other hand, large plecos can be safely mixed with smaller fish as they will not usually try to eat them.

What Do Plecostomus Eat?

While plecostomus and other suckermouth catfish are typically sold as algae eaters, some species are carnivorous, feeding on carrion in the wild. Others feed almost exclusively on wood, so it is best to research the dietary needs of any species you buy. Aqueon Bottom Feeder Tablets, Shrimp Pellets, Tropical Granules and Algae Rounds can all be excellent foods for these catfish. Because of their nocturnal habits, many experienced hobbyists target feed their plecos once or twice a week with tablet or disc foods given at night. For best results, feed a variety of high-quality foods and rotate your fishes' diet daily.

Plecostomus Breeding Level - Difficult

While not much is known about the spawning behavior of many rarer species, a fair number of suckermouth catfish have been bred in captivity. They typically spawn in caves, with the male caring for the eggs until they hatch. Fry, or recently hatched fish, are voracious and must be fed frequently on a high protein diet such as micro worms, brine shrimp nauplii, sinking tablets or disc-type foods. For intentional spawning, a separate aquarium should be set up and breeders should be fed live or frozen foods for several weeks to condition them.

Conclusion

With a little research and care, anyone can enjoy the beauty and tranquility of a freshwater aquarium. By following these tips and choosing the right fish for your setup, you'll be well on your way to creating a thriving underwater ecosystem.