Betta
Betta splendens
The Siamese fighting fish: one male per tank, warm still water, and no long-finned or nippy tank mates.
Key facts
- Body length
- 2.8 in without fins
- Minimum tank
- 11 gallons
- Group
- Alone is fine
- Temperament
- Semi-aggressive
- Care level
- 2 / 5
- Lifespan
- 3–5 years
- Diet
- Betta pellets, frozen bloodworm and brine shrimp
- Origin
- Thailand, Cambodia and Laos
- Hardier than67%
- Bigger than42%
- Calmer than28%
Water: their range vs yours
Betta tank mates
- Harlequin rasboraGets along in shared water.Good mates
- Panda corydorasGets along in shared water.Good mates
- OtocinclusGets along in shared water.Good mates
- Black neon tetraGets along in shared water.Good mates
- Blood parrot cichlidGets along in shared water.Good mates
- Bristlenose plecoGets along in shared water.Good mates
- Bronze coryGets along in shared water.Good mates
- Cardinal tetraGets along in shared water.Good mates
- Cherry barbGets along in shared water.Good mates
- Clown loachGets along in shared water.Good mates
- Common plecoGets along in shared water.Good mates
- DemasoniGets along in shared water.Good mates
- Neon tetraUsually fine in 20G+; some bettas chase.Risky
- Cherry shrimpBetta eats dwarf shrimp: Cherry shrimp (some individuals hunt them).Risky
- Amano shrimpBetta eats dwarf shrimp: Amano shrimp (some individuals hunt them).Risky
- Chinese algae eaterChinese algae eater eats slow fish: Betta (SF: присасывается к бокам крупных соседей, объедая слизь).Risky
- Convict cichlidConvict cichlid can eat young or small Betta; adults are big enough to be safe.Risky
- GoldfishGoldfish needs cool water; bettas need tropical heat.Risky
- Fancy guppyBettas attack guppies’ long fins.Avoid
- AngelfishBoth are territorial; the betta loses fins.Avoid
- Tiger barbTiger barbs nip betta fins.Avoid
- Black widow tetraBlack widows nip betta fins.Avoid
- Blue dolphin cichlidBlue dolphin cichlid can eat Betta: prey body depth 2.1 cm ≤ mouth 6.3 cm.Avoid
- Dwarf gouramiBetta attacks fish with a similar shape or colour: Dwarf gourami.Avoid
How we check
The numbers the tank model uses for bettas: water as ideal and tolerated ranges, bioload from adult mass, space, flow and how they act on other species.
- Standard length
- 7 cm (SL)
- Adult mass
- 5.14 g
- Bioload at 25 °C
- 3.47 BU
- Min. water
- 35 L net
- Min. footprint
- 45 × 30 cm per specimen
- Group
- 1+ (best 1)
- Swims in
- top, surface
- Flow
- still
- Body / fins
- labyrinth, long trailing fins
- Diet type
- carnivore
- Fin nipper
- none
- Sensitive to
- —
Sources: Seriously Fish: Betta splendens
Care notes
Bettas breathe air from the surface and like warm, calm water with leaves to rest on. A heater and a lid are not optional.
Males fight each other and flare at long-finned fish like guppies. Small, quick schooling fish usually work in 20 gallons and up.
Questions
What size tank does a betta need?
At least 11 gallons (35 litres of water after decor). Adults reach about 2.8 inches without fins.
How many bettas should be kept together?
One is fine. They do not need company of their own kind.
What water do bettas need?
72–86 °F, pH 6–7.5 and 1–15 dGH. Bettas come from Thailand, Cambodia and Laos.
How long do bettas live?
3–5 years with good care.
What fish can live with bettas?
Good tank mates include Harlequin rasbora, Panda corydoras, Otocinclus, Black neon tetra and Blood parrot cichlid. Each is checked both ways for size, fin nipping, temperament, territory and shared water.