Tank Setup
- Tank size: 30 gallons for a single fish, 55+ for a pair or with tank mates
- Substrate: Sand — firemouths are prolific diggers and sifters
- Caves: Multiple caves and hiding spots for territory. Terracotta pots, stacked rocks, and driftwood work well.
- Plants: Can work with robust plants (anubias, java fern) attached to hardscape. They will uproot anything planted in substrate.
Water Parameters
- Temperature: 75–86°F (24–30°C)
- pH: 6.5–8.0
- GH: 8–15 dGH
Behavior & Aggression
Firemouths are among the least aggressive Central American cichlids. Their famous gill-flaring display is mostly bluff — they rarely follow through with actual attacks. However, they become significantly more aggressive when:
- Breeding (both parents aggressively defend eggs and fry)
- Kept in too-small tanks
- Paired with much smaller or very passive fish
Tank Mates
- Good: Other similarly-sized Central American cichlids (in 75+ gallon tanks), large barbs, swordtails, robust catfish
- Avoid: Small tetras, guppies, shrimp, or anything they can fit in their mouth
Frequently Asked Questions
Are firemouth cichlids aggressive?
Mildly. They are one of the least aggressive Central American cichlids. Their gill-flaring display is mostly bluff. They're a great "gateway" cichlid for keepers who want to try cichlids without extreme aggression.