Convict cichlid care guide
Also called: Convict fish, Pink convict cichlid, White convict cichlid, Archocentrus nigrofasciatus, Cichlasoma nigrofasciatum
The convict cichlid is a tough, black-banded Central American cichlid that reaches about 12 cm (5 in). It is very easy to keep and breed, but it is aggressive and territorial, so it needs a roomy tank and sturdy tank mates or a tank of its own.
Convict cichlids need a tank of at least 29 gallons (110 L), and water at 24–28°C (75–82°F) with a pH of 7–8. They grow to about 12 cm (4.7 in) and are aggressive.
Plan a tank with convict cichlidsSee all tank mates
Convict cichlid quick facts
| Scientific name | Amatitlania nigrofasciata |
|---|---|
| Family | Cichlidae |
| Origin | Central America: Guatemala, El Salvador and Honduras (pink and white forms are captive-bred) |
| Adult size | 12 cm (4.7 in) |
| Minimum tank | 29 gallons (110 L), at least 90 cm (35 in) long |
| Temperature | 24–28°C (75–82°F) |
| pH | 7–8 |
| Hardness (GH) | 6–20 dGH |
| Group size | Alone or as a pair |
| Temperament | Aggressive; males fight each other |
| Swims at | Bottom |
| Diet | Omnivore |
| Care level | Easy |
| Lifespan | 8–10 years |
| Safe with shrimp? | No, eats shrimp |
| Safe with plants? | Mostly (nibbles soft plants) |
Tank setup
One fish or a pair needs at least a 30-gallon (110 L) tank about 90 cm (36 in) long, and 40 gallons (151 L) or more is better. Give them rocks and caves to claim, and use potted or rhizome plants because they dig. A strong filter helps, since they are messy eaters.
How many convict cichlids in a tank?
The smallest common tank that suits convict cichlids is a 40 gallon. Here is roughly how many fit in each size when they are the only fish, based on adult size and waste output. Leave room if you want tank mates.
| Tank | Convict cichlids (alone) |
|---|---|
| 3 gallon | Too small |
| 5 gallon | Too small |
| 10 gallon | Too small |
| 15 gallon | Too small |
| 20 gallon | Too small |
| 20 gallon long | Too small |
| 29 gallon | Too small |
| 40 gallon | Up to 6 |
| 55 gallon | Up to 9 |
| 75 gallon | Up to 13 |
| 125 gallon | Up to 21 |
Numbers are bioload limits only. Males fight, so keep one fish or one pair.
What you need for convict cichlids
Sized for a 29 gallon tank, the smallest common size that suits convict cichlids. For a different tank or a mix of fish, use the stocking calculator for a list sized to your plan.
Tank and equipment
- 29 gallon aquarium (tank or kit) (opens Amazon in a new tab)Bigger tanks are more stable and easier for beginners. How to choose
- Aquarium stand for 29 gallons (opens Amazon in a new tab)The water alone weighs about 242 lb (110 kg), before glass, gravel and rock. How to choose
- Adjustable heater, 150 W (opens Amazon in a new tab)Holds about 79 °F (26 °C) in a room at 65 °F (18 °C). How to choose
- Aquarium thermometer (opens Amazon in a new tab)Check it daily: heaters can fail stuck on or off. How to choose
- Hang-on-back filter rated 115–175 GPH (opens Amazon in a new tab)Community tank: 4–6 times the tank volume per hour. How to choose
- About 45 lb of aquarium gravel (opens Amazon in a new tab)Enough for a layer about 2 in (5 cm) deep. Smooth gravel suits most community fish. How to choose
- Water conditioner (dechlorinator) (opens Amazon in a new tab)Removes chlorine and chloramine from tap water. Seachem Prime is a popular, concentrated choice. How to choose
- Liquid test kit (ammonia, nitrite, nitrate, pH) (opens Amazon in a new tab)Liquid kits are more accurate than strips. The API Freshwater Master Test Kit is the common choice. How to choose
- Gravel vacuum (siphon) (opens Amazon in a new tab)Cleans the gravel and does the water change in one go. How to choose
- LED aquarium light, about 30 in long (opens Amazon in a new tab)Match the light to the tank length. Basic LEDs grow easy plants. How to choose
Food and extras for convict cichlids
- Sinking pellets or wafers (opens Amazon in a new tab)Bottom feeders need food that reaches the floor.
- Caves and hides (opens Amazon in a new tab)Gives shy and territorial fish their own space.
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Water parameters
Keep them at 24–28 °C (75–82 °F), pH 7.0–8.0 and 6–20 dGH. They survive a wide range, but slightly hard, alkaline water suits them best. Change about a quarter of the water each week.
Best tank mates for convict cichlids
These popular species share convict cichlids' water needs and temperament. See the full list of 10 good matches.
Nerite snail
2.5 cm (1 in) · 22–27°C (72–81°F)
Assassin snail
2.5 cm (1 in) · 22–27°C (72–81°F)
Ramshorn snail
2 cm (0.8 in) · 21–27°C (70–81°F)
Malaysian trumpet snail
2.5 cm (1 in) · 20–27°C (68–81°F)
Mystery snail
5 cm (2 in) · 21–26°C (70–79°F)
Rabbit snail
8 cm (3.1 in) · 25–29°C (77–84°F)
Jewel cichlid
10 cm (3.9 in) · 24–27°C (75–81°F)
Avoid keeping convict cichlids with
- Bristlenose pleco: Convict cichlid is aggressive and will bully or injure peaceful bristlenose plecos.
- Bronze corydoras: Convict cichlid is aggressive and will bully or injure peaceful bronze corydoras.
- Cherry shrimp: Convict cichlid eats small shrimp like cherry shrimp.
- Common goldfish: They need different temperatures: Convict cichlid 24–28°C (75–82°F), common goldfish 15–22°C (59–72°F).
- Common pleco: Convict cichlid is aggressive and will bully or injure peaceful common plecos.
- Dwarf gourami: Convict cichlid is aggressive and will bully or injure peaceful dwarf gouramis.
Feeding
Convicts eat almost anything. Feed a cichlid pellet as the staple, with frozen bloodworm or brine shrimp and some plant foods such as spirulina pellets or blanched vegetables. Small meals two or three times a day are better than one big one.
Behavior
They are bold and territorial, and a breeding pair will attack fish several times its size. Small or peaceful fish get bullied or eaten. If you want tank mates, choose robust fish of a similar size in a large tank, and give every fish its own cover.
Breeding
Convicts breed so readily that one pair can fill a tank with fry. The female lays up to a few hundred eggs in a cave, and both parents guard the young fiercely. Eggs hatch in about 3–4 days, and the fry swim freely within about a week of hatching. Have a plan for the young before you keep a male and female together.
Tips from experienced keepers
- Keep a single convict if you don't want fry. A male and female will breed again and again.
- Don't add small fish such as neon tetras. Adult convicts eat them.
- Build several caves and rock piles so each fish or pair has its own space.
- Use Java fern, Anubias or potted plants, since convicts dig up rooted plants.
- Move fry out once they are swimming well, before the parents turn on each other or the young.
Frequently asked questions
Are convict cichlids aggressive?
Yes. They are among the most aggressive small cichlids, especially when breeding, and they chase and injure peaceful community fish.
How big do convict cichlids get?
Males usually reach about 12–15 cm (5–6 in). Females stay smaller, around 10–11 cm (4 in), and often show orange on the belly.
What size tank does a pair of convict cichlids need?
At least 30 gallons (110 L) in a tank about 90 cm (36 in) long. A 40-gallon (151 L) tank gives more room and fewer fights, and you need more space for tank mates.
Sources
We checked these references when writing this page. Values are for healthy long-term keeping, not survival limits. Last reviewed 2026-10-13. See our editorial policy.