Tank Setup
- Tank size: 30 gallons for a single fish, 55+ for a pair (they WILL breed)
- Caves: Multiple caves and territory markers. Convicts are cave spawners and will aggressively defend their chosen cave.
- Substrate: Sand or gravel — they dig constantly
- Plants: They will destroy most plants. Use only hardy, attached plants if any.
Water Parameters
- Temperature: 72–82°F
- pH: 6.5–8.0
- GH: 8–20 dGH
Convicts are among the hardiest freshwater fish. They tolerate a wide range of water conditions and are nearly impossible to kill through water parameter issues alone.
Breeding — The Convict Problem
Convict cichlids are legendary breeders. A male-female pair will breed every 3–4 weeks, producing 100–300 fry each time. Both parents are exceptional, ferociously protective parents that will attack anything — including your hand — that comes near their fry.
The "convict problem" is that most fishkeepers cannot rehome the constant stream of babies. Consider carefully before keeping a pair. Options include:
- Keeping only one sex (though sexing juveniles is difficult)
- Keeping a single convict (they have plenty of personality solo)
- Adding egg-eating tank mates that control population naturally
Aggression Management
Convicts punch way above their weight class. A 4-inch convict will fearlessly attack fish twice its size. Their aggression escalates dramatically when:
- Breeding or guarding fry (both parents become extremely aggressive)
- Tank is too small
- Paired with timid fish that can't defend themselves
Tank Mates
Only with other robust, aggressive fish of similar or larger size:
- Other Central American cichlids (firemouths, Jack Dempseys in large tanks)
- Large, armored catfish (common pleco, bristlenose)
- Silver dollars, large barbs
Never with any small or peaceful species.
Frequently Asked Questions
Can convict cichlids live alone?
Yes, and this is often the best option. A single convict in a 30-gallon tank displays all their personality without the complications of constant breeding.
How do I stop my convicts from breeding?
Keep only one sex, keep a single fish, or add robust egg-eating tank mates. Once a pair forms, they will breed continuously and there is no way to stop them short of separation.