African butterflyfish
Semi-aggressive · Top · moderate care
- 5 in adult
- 30+ gal
- 73–86 °F
- pH 6.5 to 7.5
- alone or pair
Types of oddball fish
14 bichirs, knifefish and other oddballs compared at one scale: adult size, the tank they need, temperature and group size.
Black ghost knifefish
Semi-aggressive · Bottom · demanding care
- 20 in adult
- 125+ gal
- 73–82 °F
- pH 6 to 7.5
- alone or pair
Clown knifefish
Semi-aggressive · Middle · demanding care
- 39 in adult
- 250+ gal
- 75–82 °F
- pH 6 to 7.5
- one per tank
Elephantnose fish
Peaceful · Bottom · demanding care
- 9 in adult
- 55+ gal
- 77–82 °F
- pH 6.5 to 7.5
- alone or pair
Everglades pygmy sunfish
Peaceful · Bottom · moderate care
- 1.3 in adult
- 5+ gal
- 55–80 °F
- pH 6.5 to 7.5
- groups of 2+
Fire eel
Semi-aggressive · Bottom · demanding care
- 39 in adult
- 180+ gal
- 75–82 °F
- pH 6.5 to 7.5
- alone or pair
Indian glassfish
Peaceful · Middle · moderate care
- 3.1 in adult
- 20+ gal
- 72–82 °F
- pH 7 to 8
- groups of 6+
Ornate bichir
Semi-aggressive · Bottom · moderate care
- 24 in adult
- 180+ gal
- 75–82 °F
- pH 6.5 to 7.5
- alone or pair
Peacock eel
Peaceful · Bottom · moderate care
- 12 in adult
- 55+ gal
- 73–82 °F
- pH 6.5 to 7.5
- alone or pair
Ropefish
Peaceful · Bottom · moderate care
- 15 in adult
- 55+ gal
- 75–82 °F
- pH 6.5 to 7.5
- alone or pair
Scarlet badis
Peaceful · Bottom · moderate care
- 0.8 in adult
- 10+ gal
- 72–79 °F
- pH 6.5 to 7.8
- one male per tank
Senegal bichir
Semi-aggressive · Bottom · easy care
- 14 in adult
- 75+ gal
- 75–84 °F
- pH 6.5 to 7.5
- alone or pair
Silver arowana
Semi-aggressive · Top · demanding care
- 36 in adult
- 250+ gal
- 75–82 °F
- pH 6 to 7.5
- one per tank
Zig-zag eel
Semi-aggressive · Bottom · moderate care
- 20 in adult
- 55+ gal
- 72–82 °F
- pH 6.5 to 7.5
- one per tank
No species on this list match those filters. Try a larger tank or clear a filter.
Other fish families
Types of plecosTypes of aquarium shrimpTypes of aquarium snailsTypes of tetrasTypes of rasboras and daniosTypes of barbsTypes of livebearersTypes of bettas and gouramisTypes of cichlidsTypes of catfishTypes of loachesTypes of freshwater sharksTypes of rainbowfishTypes of killifishTypes of puffersTypes of goldfishTypes of shrimp, snails, frogs and axolotlsAll fish
Names, and adult sizes where the article gives one, are checked against Wikipedia; care ranges are common hobby guidance, and each species page says which is which. 14 of these 14 are fish. Photos are real photographs from Wikimedia Commons, credited below; the lineup is our own drawing at one scale.
Photo credits
Real photographs from Wikimedia Commons, resized and cropped to fit; each is used under the license named.
- African butterflyfish Toniher, CC BY-SA 3.0, via Wikimedia Commons
- Black ghost knifefish Vassil, CC0, via Wikimedia Commons
- Clown knifefish Parkourprincess, CC BY-SA 4.0, via Wikimedia Commons
- Elephantnose fish Jutta234, CC BY-SA 3.0, via Wikimedia Commons
- Everglades pygmy sunfish Brian Gratwicke, CC BY 2.0, via Wikimedia Commons
- Fire eel Llandor, CC BY-SA 3.0, via Wikimedia Commons
- Indian glassfish opencage, CC BY-SA 2.5, via Wikimedia Commons
- Ornate bichir Bloopityboop, CC BY-SA 4.0, via Wikimedia Commons
- Peacock eel Zachary Randall, Florida Museum, CC BY 4.0, via Wikimedia Commons
- Ropefish Michał Zalewski, CC BY-SA 3.0, via Wikimedia Commons
- Scarlet badis ATuin-hek, CC0, via Wikimedia Commons
- Senegal bichir Zhyla at English Wikipedia, CC BY-SA 3.0, via Wikimedia Commons
- Silver arowana Qwertzy2, CC BY-SA 3.0, via Wikimedia Commons
- Zig-zag eel Adolsomee, CC BY-SA 3.0, via Wikimedia Commons
