Rainbow shark care
Epalzeorhynchos frenatum · Mekong, Chao Phraya and Xe Bangfai basins
Rainbow sharks are dark fish with red fins that claim a territory at the bottom of the tank.
- Tank size
- 55 US gal or larger
- Temperature
- 72 to 80 °F (22 to 27 °C)
- Group size
- Alone (one per tank)
- Temperament
- Semi-aggressive
- Adult size
- 6 in
- pH
- 6.5 to 7.5
- Hardness (GH)
- 4 to 15 dGH
- Lifespan
- 5 to 8 years
- Diet
- Omnivore
- Care level
- Easy
In a 55 gallon
48¼ × 12¾ × 21 in outsideHow to keep rainbow sharks
Rainbow sharks are dark fish with red fins that claim a territory at the bottom of the tank. Keep one per tank, in a 55 gallon or larger with caves, and avoid other bottom fish of similar shape.
Diet: Omnivore: sinking pellets, algae wafers, vegetables, frozen foods. Fish food types compared · how often to feed.
Where they swim: Bottom of the tank.
Rainbow shark tank mates
Share the temperature and water, and neither side eats, nips or bullies the other. Check the full group in the stocking checker.
Angelfish
6 in · 29+ gal · 76–84 °F
Giant danio
6 in · 55+ gal · 72–79 °F
Rosy barb
6 in · 29+ gal · 64–77 °F
Denison barb
6 in · 55+ gal · 64–77 °F
Three-spot (blue) gourami
6 in · 29+ gal · 72–82 °F
Electric blue acara
6 in · 40+ gal · 72–82 °F
Silver dollar
6 in · 75+ gal · 75–82 °F
Scissortail rasbora
6 in · 40+ gal · 72–79 °F
Keep apart
Discus: No shared temperature: rainbow sharks need 72 to 80 °F, discus 82 to 88 °F.
Pea puffer: Pea puffers belong in a tank of their own.
African dwarf frog: African dwarf frogs are slow and get bullied or outcompeted by rainbow sharks.
Demasoni cichlid: Demasoni cichlids belong with other Lake Malawi cichlids, not with rainbow sharks.
Red zebra cichlid: Red zebra cichlids belong with other Lake Malawi cichlids, not with rainbow sharks.
Flowerhorn cichlid: Flowerhorn cichlids belong in a tank of their own.
What a rainbow shark tank needs
A tank of 55 US gallons or more (such as the 55 gallon) with a tight lid (they jump), and the equipment below.
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Aqueon QuietFlow Canister Filter 200
Rated by the maker for up to 55 US gal, which covers a 55 gallon rainbow shark tank without being built for a far bigger one.
Seachem Tidal 55
Rated by the maker for up to 55 US gal, which covers a 55 gallon rainbow shark tank without being built for a far bigger one.
Aqueon Pro 150
Rainbow sharks need 72 to 80 °F; most homes run cooler, so a heater holds the temperature.
API Freshwater Master Test Kit
Tests ammonia, nitrite, nitrate and pH, the readings that matter most before and after adding rainbow sharks.
Seachem Prime 100 mL
Removes chlorine and chloramine from tap water at every water change.
Fluval Edge Thermometer
Shows the water temperature at a glance, so you know it stays within 72 to 80 °F.
More choices, each with the reason it is in or out: Filters for a 55 gallon tank · Heaters for a 55 gallon tank. We don’t list fish food: any good brand of the foods under Diet will do. Plan the whole tank's equipment →
Common rainbow shark problems
- Two sharks, or a red-tail and a rainbow shark, fight.
Test the water first whenever fish look unwell: see what your readings mean, then match the symptom. For disease, a vet who treats fish can diagnose it and advise treatment.
More to compare
Sources
Name, origin and adult size checked against Wikipedia: Epalzeorhynchos frenatum. Temperature, pH, hardness, group size, lifespan and minimum tank size are common hobby guidance, not figures from that article. Ranges are the range the species tolerates; aim for the middle. Minimum tank sizes are for an adult group. Drawings are our own; photo credits follow.
Photo credits
Real photographs from Wikimedia Commons, resized and cropped to fit; each is used under the license named.
- Rainbow shark MerlinSenger, CC BY-SA 3.0, via Wikimedia Commons
- Angelfish Citron, CC BY-SA 3.0, via Wikimedia Commons
- Giant danio Faucon, CC BY-SA 2.5, via Wikimedia Commons
- Rosy barb Kkonstan, CC BY 3.0, via Wikimedia Commons
- Denison barb Anandarajkumar, CC BY-SA 3.0, via Wikimedia Commons
- Three-spot (blue) gourami Peter Jung, CC BY-SA 3.0, via Wikimedia Commons
- Electric blue acara 5snake5, CC0, via Wikimedia Commons
- Silver dollar Greg Hume, CC BY-SA 4.0, via Wikimedia Commons
- Scissortail rasbora Lerdsuwa, CC BY-SA 3.0, via Wikimedia Commons
- Discus Patrick Farrelly, Public domain, via Wikimedia Commons
- Pea puffer Beta Mahatvaraj, CC BY-SA 4.0, via Wikimedia Commons
- African dwarf frog Stuart Halliday, CC BY 3.0, via Wikimedia Commons
- Demasoni cichlid lee Nachtigal, CC BY 2.0, via Wikimedia Commons
- Red zebra cichlid Maha Dinesh, CC BY-SA 3.0, via Wikimedia Commons
- Flowerhorn cichlid Lerdsuwa, CC BY-SA 3.0, via Wikimedia Commons
- Red-tail shark Astellar87, CC BY-SA 4.0, via Wikimedia Commons
- Bala shark H. Zell, CC BY-SA 3.0, via Wikimedia Commons
- Iridescent shark Melanochromis, CC BY-SA 3.0, via Wikimedia Commons
