Can you have a shark as a pet? While ocean-swimming varieties are too large for hobby tanks, there are many types of pet sharks suitable for freshwater aquariums and ponds. We’ve rounded up the most popular species and created this detailed care guide to help you design the best tank for your freshwater aquarium sharks.
freshwater shark guide for fish tanks
If you are a fan of Shark Week, then you should consider having sharks as pets for your home aquarium. These predatory fish are fascinating to watch and make for an active and lively aquatic display. How are pet mini sharks different from the larger saltwater varieties, and what type of tank and care do they require?
What is a freshwater aquarium shark?
Domesticated sharks are not true sharks, but fish that look like sharks. There are a wide variety of shark-like fish that make great aquarium pets, and some are even great for community tanks! These small freshwater shark species share some similarities with each other:
- Mini sharks have long, torpedo-shaped bodies and prominent, upright dorsal fins. It is also common to see deeply forked tail fins (tails) in freshwater sharks.
- They are usually members of the catfish or carp families and act as omnivorous scavengers, eating plant materials such as algae and other animals.
- Sharks are often active and entertaining pets that enjoy swimming in strong currents, and many species congregate if kept in a group.
How big are freshwater sharks?
Pet sharks for home aquariums are usually sold as juveniles when they are a few inches long and can take several years to reach full size. It’s easy to underestimate how big they can grow, so always keep their maximum adult size range in mind when designing your shark tank.
The smallest aquarium sharks reach about half a foot in length as adults, while larger varieties can reach 3 to 4 feet depending on their habitat and diet. Aquarium sharks rarely reach their full size if they are kept in crowded conditions and fed a poor quality diet.
How to Set Up a Shark Aquarium
There are many questions that come up when looking to set up a shark tank. What size tank do you need for a shark and what type of filtration system do they prefer? Here are the key requirements for designing a stellar freshwater shark aquarium!
Tank size and environment
Most freshwater sharks are native to fast-flowing streams and rivers and need plenty of room to swim. They generally do better in long style tanks rather than cube or portrait forms. Bottom-dwelling sharks also like to have rocks, caves, and plants to explore, while mid-level and surface sharks prefer open tanks with fewer decorations.
In terms of capacity, the ideal freshwater shark tank is at least 100 gallons:
- There are few shark species that can thrive in 20 to 55 gallon tanks, as long as there are not too many fish; ideal numbers vary depending on the species.
- While you can temporarily raise juveniles in smaller facilities, there are no shark varieties small enough for 10-gallon tanks as adults.
- Some types of freshwater sharks are better suited to life in a pond than an aquarium at maturity, unless you have a 300 to 500 gallon tank.
Filtration and water requirements
One thing all freshwater shark species have in common is sensitivity to water conditions. It is important to do regular weekly water changes and vacuum the gravel well to remove decomposing materials. If you want to have healthy predatory fish:
- Sharks need very fresh, filtered water, free of detectable ammonia or nitrates.
- Weekly water changes and regular filter maintenance and media replacement are necessary to keep the tank free of decaying materials that can cause nitrogen spikes.
- They also need stable water parameters, so you’ll need to maintain a consistent water temperature and test the pH regularly to avoid problems.
You should definitely invest in a top-tier aquarium filter that can handle a high flow rate. Sharks enjoy swimming in strong currents and prefer highly oxygenated waters. For most shark tanks, a canister filtration system is an ideal choice, as it is easier to direct the outflow to generate strong currents than with a HOB-style filter.
In terms of temperature, most freshwater sharks are tropical fish that need their water to stay in the 70-80°F range. You will need a heater for most shark tanks, although there are some cold water sharks that do not need additional heat and do well in pond environments.
Substratum
It is generally best to choose a substrate that matches the natural environment of your freshwater shark species. Many of these fish are bottom dwellers of the catfish family and have delicate barbels or whiskers that could be injured on sharp rocks or gravel. Soft sand is ideal for most shark tanks, but some species do well with gravel as well.
How And What To Feed Your Freshwater Shark
Unlike their large carnivorous cousins in the ocean, freshwater sharks are omnivorous scavengers that will eat anything that fits in their mouths. They are also generally not picky about their diets. Your sharks will eat smaller fish and invertebrates like shrimp just as easily as they will eat commercial diets and algae.
How Often Should You Feed Your Shark?
With their voracious appetites, it is best to feed sharks 2-3 times a day when they are juveniles and at least once a day when they are adults. The exact amounts will vary, of course, but you should limit it to what they can consume in about 2-3 minutes and quickly dispose of any leftovers.
What is the best diet for freshwater sharks?
The best commercial shark diets are usually high- protein omnivorous diets made for catfish, goldfish, and koi.
- For bottom feeding shark species, sinking pellets or wafers are ideal as they fall naturally to the bottom of the tank where the shark is located.
- For mid-level and surface sharks, floating flake or pellet diets are perfect as they stay in the water column for a while.
The best treats depend on your species of shark, but should include a mix of live/frozen foods and protein-rich plant products. Some options include:
- Brine shrimp, mysis shrimp, krill and other crustaceans.
- Bloodworms, tubifex worms, and earthworms.
- Insects, larvae and eggs, such as mosquito larvae and Daphnia eggs or fry.
- Algae wafers, spirulina granules and sinking vegetable granules.
- Fresh blanched green vegetables like spinach, cucumber, zucchini, and peas.
Freshwater Sharks You Can Have: 13 Little Sharks For Aquariums
Now that you know how to design the ideal shark tank and the details on its care and feeding, let’s take a look at the best small shark species for aquariums and freshwater ponds! This list of freshwater sharks includes some of my favorites, as well as some rare and extremely unique fish for advanced aquarists.
1. Rainbow shark
One of the most popular freshwater sharks is the impressive and entertaining bottom dweller known as the Rainbow Shark. With their long bodies and dark gray to black scales, their bright red fins really stand out among the plants and decorations in your tank. You will see why they are also known as the Ruby Shark.
Rainbow sharks are semi-aggressive and territorial, needing at least 50 gallons free from other bottom-dwelling species. They can be shy when young, but become more aggressive as they mature. They prefer a densely planted tank with some open areas to swim in, with lots of rocks or logs to hide in. They are active during the day and always come out at feeding time.
| Scientific name | Epalzeorhynchos frenatus |
| Common names | Rainbow Shark, Ruby Shark |
| Family | cyprinids |
| Temper | Semi-Aggressive and Territorial |
| Level of attention | easy to moderate |
| Minimum tank size | 50 gallons for 1; 125 gallons for a group of 3 |
| maximum adult length | 6 inches |
| Shark Color and Appearance | Dark gray to black body with orange/red fins and black eyes. |
| water conditions | 75 to 81°F; pH 6.5 to 7.5; 5 to 11 KH |
| Diet | Omnivore; enjoy a variety of flake, fresh, frozen and freeze-dried treats |
| Compatible Tank Mates | Mid-tier and higher-tier fish that don’t look like sharks and are too big to eat, such as Gourami, Barbs, Danios, and Rainbowfish |
2. Albino rainbow shark
The Albino Rainbow Shark is a rare color morph that is a joy to keep in a large planted tank. They are identical to regular Rainbows in size and shape, but their bodies are white with pink highlights around their gills and abdomens. Their fins are a pinkish-orange color instead of being a deep red. However, their behavior and care requirements are the same as the normal Rainbow Shark.
Albinos look amazing as they dig through the substrate for food and chase other fish from their territories. They generally prefer a soft sandy bottom to prevent injury to their delicate scales and enjoy swimming in swift currents along the bottom of their tank. If you want to have more than one fish, you’ll need at least a 125-gallon shark tank so they each have room to establish their territory.
| Scientific name | Epalzeorhynchos frenatus |
| Common names | albino rainbow shark |
| Family | cyprinids |
| Temper | Semi-Aggressive and Territorial |
| Level of attention | easy to moderate |
| Minimum tank size | 50 gallons for 1; 125 gallons for a group of 3 |
| maximum adult length | 6 inches |
| Shark Color and Appearance | White body with pink/orange/red fins and red/pink eyes. |
| water conditions | 75 to 81°F; pH 6.5 to 7.5; 5 to 11 KH |
| Diet | Omnivore; enjoy a variety of flake, fresh, frozen and freeze-dried treats |
| Compatible Tank Mates | Medium and high level fish that do not look like sharks. Gourami, barbs, danios and rainbow fish |
3. Bala Shark
One of my favorite aquarium species in general is the beautiful Bala Shark. Don’t let their impressive black and yellow dorsal fin fool you into thinking they’re evil! These sharks are peaceful members of the community as long as they are kept with fish large enough that they cannot be eaten.
Bala Sharks make a great addition to community planted tanks and can sometimes be kept with other shark species as well. They enjoy group education in the middle of their tank and generally ignore bottom dwellers. However, they can grow up to a foot long, so each shark needs at least 45 gallons of space. Leave plenty of open areas with a fast current for swimming, and your Bala will put on quite a show, especially during feedings!
| Scientific name | Balantiocheilus melanopterus |
| Common names | Bala Shark, Silver Shark |
| Family | cyprinids |
| Temper | peaceful and active |
| Level of attention | Moderate |
| Minimum tank size | 150 gallons for a group of 3 (at least 45 gallons per shark) |
| maximum adult length | 12 inches |
| Shark Color and Appearance | Silver/gray body with distinctive black and yellow stripes on fins and large black eyes |
| water conditions | 76 to 80°F; pH 6.5 to 8; not sensitive to hardness |
| Diet | Omnivore; high-protein flake or pellet diet supplemented with fresh/frozen bloodworms and brine shrimp |
| Compatible Tank Mates | Ideal for peaceful aquatic communities with large fish such as other Bala Sharks, Gourami, Rainbowfish, Corydoras and Tetras |
4. Rosaline Torpedo Shark
I have had Rosaline Torpedo Sharks in my community tanks for years and didn’t even know it. Turns out these sharks are more commonly known as Denison’s Barb, which is the name I bought them by. These bright and active sharks love to go to school in a group in the middle of your tank, and their black and red stripes and yellow and black dorsal and tail fins add lots of color to your tank.
These active swimmers need clean, highly oxygenated water with plenty of areas open to school. They are best kept in groups of 6 or more and often misbehave when kept in smaller numbers. They are messy eaters and often uproot plants, so more abundant varieties like Anubis and Java Fern are ideal if you are opting for a community of planted sharks.
| Scientific name | Sahyadria denisonii |
| Common names | Rosaline Torpedo Shark, Denison’s Barb, Red-Line Torpedo Barb |
| Family | cyprinids |
| Temper | peaceful and active |
| Level of attention | Moderate |
| Minimum tank size | 55 gallons for a group of 6 |
| maximum adult length | 6 inches |
| Shark Color and Appearance | Silvery/gray body with a prominent black stripe running from head to base of tail and a red stripe above it through the eye and part of the body. It has a bright red dorsal fin and yellow/black stripes on the tips of the caudal fins. |
| water conditions | 60 to 77°F; pH 6.8 to 7.8; 5 to 25 dGH |
| Diet | Omnivore; Enjoy a wide variety of flake, granule and fresh/frozen foods |
| Compatible Tank Mates | Best kept in schools of 6 or more with other large community fish such as Barbs, Danios, Tetras or Cichlids |
5. Red-tailed black shark
A distant relative of the Rainbow are these impressive red-tailed black sharks. Its general shape is similar to that of its cousins, but its scales and fins are deep black, highlighting its deep red caudal fin (tail). These semi-aggressive bottom dwellers defend their territories and usually ignore the rest of the tank.
Red tail sharks are a bit more difficult to keep than rainbow sharks as they are a bit more aggressive towards other fish that enter their territories. But unlike the Rainbow, they rarely target fish that stay in the middle of their tank. I kept Red-Tails with Bala Sharks, for example, but couldn’t do the same with Rainbows. You’ll want to make sure they are your only bottom-feeding fish to avoid aggression issues.
| Scientific name | Epalzeorhynchos bicolor |
| Common names | red tail black shark, red tail shark |
| Family | cyprinids |
| Temper | Semi-Aggressive and Territorial |
| Level of attention | Moderate |
| Minimum tank size | 55 gallons per shark |
| maximum adult length | 6 inches |
| Shark Color and Appearance | Black body scales with bright red tail fins. |
| water conditions | 72 to 79°F; pH 6.8 to 7.5; 5 to 15 dH |
| Diet | Omnivore; Commercial flakes and pellets, sinking algae wafers, fresh/frozen bloodworms, brine shrimp or krill |
| Compatible Tank Mates | Large mid-tier community fish like Bala Sharks, Angelfish, Barbs, Danios, and Tetras |
6. Harlequin Shark
Unlike the others I have profiled so far, the harlequin shark is not a peaceful or semi-aggressive species. They are very aggressive and easily attack other species, even other harlequins. These rare camouflaged bottom dwellers prefer densely planted tanks with few tank mates and a fast current. They are ideal for large single species installations 55 gallons and up.
Harlequin sharks should only be added to mature planted aquariums because they enjoy feeding on biofilm, which is a type of algae and bacteria mix that only builds up in older tanks. These African carp live along river bottoms in the wild and thrive in tanks with a slimy substrate and plenty of rocks, sticks, and branches to hide in. They resemble some of the more conspicuous plecostomus, with their cream-colored base covered in dark gray or brown spots.
| Scientific name | Labeo cyclorhynchus |
| Common names | harlequin shark; Harlequin Sharkminnow, Variegated Shark |
| Family | cyprinids |
| Temper | highly aggressive |
| Level of attention | Moderate to Advanced |
| Minimum tank size | 55 gallons |
| maximum adult length | 6 inches |
| Shark Color and Appearance | Cream base color covered with mottled grey/brown flecks |
| water conditions | 72 to 81°F; pH 6.0 to 7.5; 3 to 15 dGH |
| Diet | Omnivore; Flake and dipping diets, fresh/frozen brine shrimp, bloodworms and mosquito larvae along with plenty of vegetables such as seaweed wafers, blanched spinach, cucumbers and chopped fruit |
| Compatible Tank Mates | It is best kept in a single species tank or with a few large mid-tier aquarium fish such as Barbs, Danios or African Characins. |
7. Siamese Algae Eater (SAE)
If you want an easy going shark that will be a great addition to any peaceful aquarium community, consider the Siamese Algae Eater (SAE). Not only do they resemble small sharks, with their long bodies and large vertical dorsal fins, but they are also one of the best algae eaters. They are one of the few fish that will eat the dreaded black hair algae!
It is not ideal to keep SAE with long-finned or slow-swimming fish like Angelfish or Bettas, as they enjoy nipping at your fins. However, SAEs are a great choice for active community tanks with a mix of planted and open areas, and they are one of the few freshwater sharks that can live in a 20 gallon nano tank!
| Scientific name | oblong channa |
| Common names | Siamese algae eater, SAE |
| Family | cyprinids |
| Temper | Peaceful and Active; can bite the tails of long-finned fish |
| Level of attention | Easy |
| Minimum tank size | 20 Gallons (add 10 wedges per SAE) |
| maximum adult length | 6 inches |
| Shark Color and Appearance | Pale gray to gold body scales with a black stripe across the eye and down the center of the tail fins |
| water conditions | 75 to 79°F; pH 6.5 to 8; 5 to 20KH |
| Diet | Omnivore; Will readily consume aquarium algae, commercial flake and pellet diets, but prefers live/frozen foods such as brine shrimp, grubs, bloodworms, and Daphnia eggs. |
| Compatible Tank Mates | Best kept with peaceful small-finned community fish such as other SAEs, Tetras, Barbs, guppies, Gourami, and Corydoras. |
8. Black minnow
Another option for experienced aquarists with very large tanks are the incredible 2-3 foot long Black Sharkminnow. These black freshwater sharks are very aggressive and do not do well in mixed or community tanks. They will quickly outcompete almost all other fish in the community and end up eating them.
What kind of tank do you need to raise these big black sharks? Like the Harlequin, they need a mature environment with plants, fast-moving currents, and plenty of open swimming areas. Juveniles can be started in a spacious 125 gallon setup, but need at least a 200 gallon tank or heated pond when they mature. A large tank with one of these monsters could be an awesome talking point in your home.
| Scientific name | Labeo chrysophekadion |
| Common names | Black Sharkminnow, Black Laebo, Great Black Shark |
| Family | cyprinids |
| Temper | highly aggressive |
| Level of attention | Advanced |
| Minimum tank size | 125 gallons for minors and at least 200 gallons for adults |
| maximum adult length | 24 to 36 inches |
| Shark Color and Appearance | Black body and fins |
| water conditions | 76 to 82°F; pH 6.5 to 7.5; 10 to 15KH |
| Diet | Omnivore; Likes to eat aquarium algae, but also needs a good commercial flake/pellet diet supplemented with plenty of live/frozen tubifex, bloodworms, brine shrimp, daphnia, and vegetables such as spinach, shelled peas, and cucumber. |
| Compatible Tank Mates | Best kept alone as the only species in a mature planted tank |
9. Iridescent Shark Catfish
If you want a large tame shark for a tank of at least 300 gallons, then take a look at the lovely and peaceful Iridescent Shark Catfish. Also known as the Siamese shark, these silver-colored fish have prominent barbels or whiskers around their mouths and can grow up to 4 feet long.
The iridescent is a difficult and challenging shark to keep in a long-term aquarium due to its size and activity, and might do best in a temperature-regulated outdoor pond. They can be reactive to noise around their tanks and often panic and injure themselves by hitting glass. They are best kept with other iridescent fish of similar size or large communities that prefer a sandy substrate and fast-flowing current.
| Scientific name | Pangasianodon hypophthalmus |
| Common names | Iridescent Shark Catfish, Siamese Shark, Sutchi Catfish |
| Family | Pangasiidae |
| Temper | peaceful and active |
| Level of attention | Advanced |
| Minimum tank size | 100 gallons for juveniles; 300 gallons per adult |
| maximum adult length | 48 inches |
| Shark Color and Appearance | Dorsal side darker gray turning pale gray or silver below lateral line |
| water conditions | 72 to 79°F; pH 6.5 to 7.5; 2 to 20 dGH |
| Diet | Omnivore; Easily eat commercial flake and pellet diets along with fresh/live foods |
| Compatible Tank Mates | Best kept with large, peaceful community fish or other similarly sized iridescent sharks |
10. Silvery Apollo Shark
The Silvery Apollo Shark is a rare fish that is often confused with its larger relative, the Longfin Apollo Shark (Luciosoma spilopleura). These peaceful fish have a pointed snout, unlike most freshwater sharks, and very short barbels or whiskers around the mouth. They prefer to swim in the middle and feed at the top of their tank.
You will need a large tank with a swift surface current to breed these sharks, and they do best in groups of 3-12. If you like, you can have Silver Apollo’s in a school with Bala Sharks, which makes for an impressive monitor. Just make sure your tank has a tight lid, because these sharks can easily jump out if there are any gaps.
| Scientific name | luciosoma setigrum |
| Common names | Silvery Apollo Shark |
| Family | cyprinids |
| Temper | peaceful and active |
| Level of attention | Advanced |
| Minimum tank size | 120 gallons for a group of 3 |
| maximum adult length | 8 to 9 inches |
| Shark Color and Appearance | Silvery/gray body with a greenish tint to the black lateral line that runs from its pointed snout to the upper edge of its forked tail fins. |
| water conditions | 72 to 78°F; pH 6.0 to 7.5; 2 to 20 dGH |
| Diet | Omnivore; Commercial flakes and floating pellets supplemented with live/frozen brine shrimp, bloodworms, krill and Mysis shrimp |
| Compatible Tank Mates | Best kept in schools of 3 to 12 along with large community fish such as Bala Sharks or Tin Foil Barbs. |
11. Blushing Violet Shark
If you want a shark that looks different from the rest, these beautiful Violet Blushing Sharks could be the bottom feeder you’ve been looking for. Their transparent albino scales allow you to see their gills through the transparent gill cover, which is why they are also called the Purple or Red Shark.
The Blushing Shark is a peaceful fish that does not usually cause problems in your tank. They can get very large, almost a foot long, making them ideal for aquariums 125 gallons and up. You can keep a single shark or raise a group of at least 5 in a larger tank. They don’t do well in smaller groups, but they make a great solo or group addition to Rainbowfish and Loach tanks!
| Scientific name | labeo vogue |
| Common names | Purple blushing shark, Purple gill shark, Red gill shark |
| Family | cyprinids |
| Temper | peaceful and active |
| Level of attention | Moderate to Advanced |
| Minimum tank size | 125 gallons |
| maximum adult length | 12 inches |
| Shark Color and Appearance | Transparent scales appearing pale pink to silver/white with pink/red gills visible through clear gill cover |
| water conditions | 68 to 78°F, pH 6.6 to 7.9 |
| Diet | Omnivore; Prefers sinking foods like algae wafers and commercial catfish pellets and fresh/frozen treats like bloodworms, brine shrimp, mosquito larvae, and blanched vegetables |
| Compatible Tank Mates | Can be kept alone in community tanks with similarly sized rainbowfish and bothiid loaches, or in single species tanks in groups of 5 or more |
12. Colombian Shark
One of the best sharks for freshwater aquariums is not a freshwater fish at all. The Colombian shark is a type of ocean catfish. They live in freshwater streams when they are young and migrate to the ocean when they mat
