Can Betta Fish Live With Clown Killifish?
No, both bettas and clown killifish are surface-dwelling carnivores that compete for territory at the top of the tank, and the outcome is bad either way.
Why
- Bettas are top-dwellers that claim the surface as their territory and will attack anything that trespasses, including clown killifish.
- Clown killifish hover at the surface in the top inch of water, which places them directly in a betta's defended zone.
- Clown killifish reach only 1.2-1.4 inches, so even a non-aggressive betta can injure them with a single charge.
- Killifish may nip at a betta's long fins out of stress or perceived competition, and the betta may attack killifish that encroach on surface territory.
What could go wrong
Either the betta chases and harasses the killifish until they stress to death, or the killifish get injured by the betta's retaliatory attacks when fins are nipped.
If you keep them in separate tanks
Sized for the 5 gallon minimum this pairing needs. Affiliate links — we earn a small commission if you buy through them.
AquaClear 20 Power Filter
Rated for up to 5 gallons with enough biological media to handle the waste from both species.
Hitop 50W Adjustable Aquarium Heater
Holds a steady temperature inside the 76-79°F window both species need.
API Freshwater Master Test Kit
Keep ammonia, nitrite, and nitrate in check. Two-species tanks have more bioload and less margin for error than single-species setups.
Better pairings to consider
Bettas do well with nerite snails, mystery snails, and cherry shrimp in nano tanks. Clown killifish do well with ember tetras, celestial pearl danios, and pygmy corydoras in a planted 10-gallon.
Related compatibility questions
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