


How to Start a Jack Dempsey Aquarium Tank

i Stockbyte/Stockbyte/Getty Images

The Jack Dempsey (Heros octofasciatus) is a large Central America cichlid named after the famous boxer of the same name. These fish received their name for the pugnacious temperament. Their large size and aggressive behavior requires specific tank requirements.

Water Chemistry

These cichlids are not extremely particular about their water conditions, beyond it being clean. They do their absolute best in moderately hard water, with a somewhat alkaline pH of 7.2 to 7.6. In general, these fish should be kept at 70 to 75 degrees Fahrenheit. If you want to breed them, raising the temperature to 80 to 83 degrees Fahrenheit can help trigger spawning. Keeping cichlids at temperatures at the low end of their temperature ranges can help diffuse aggression.

Tank Setup

Jack Dempseys make it hard to decorate their tank. They like to dig and will destroy and eat live aquarium plants. With this in mind, they should have a deep gravel bed. Any rockwork should be planted firmly on the tank bottom to keep them from knocking it over and breaking the tank. Floating, usually plastic aquarium plants are the best option for this species. They also grow up to a foot long, so a larger tank of 50-70 gallon is recommended.


Jack Dempseys can share a tank. However, if they're sharing it with other large cichlids, it needs to be at least six feet long to give them room. Large, preferably armored catfish like large plecos can make good tank-mates. Mid-water schooling fish like silver dollars and tinfoil barbs can also share a tank since they tend to avoid the bottom, the part of the tank cichlids consider their territory.


Jack Dempseys are not particular about their diet. In the wild, they eat invertebrates like snails, crustaceans and small fish. In a fish tank, they do not need live food to survive, but will appreciate the occasional treat. In captivity, you can get them to eat frozen fish foods and cichlid pellets. These items are available at most pet shops.