Comprehensive Guide to Jack Dempsey Cichlid Care: Origin, Behavior, and Tank Requirements

Size, Tank Conditions, and Lifespan

The Jack Dempsey Cichlid, native to the Yucatan Peninsula, Guatemala, and Honduras, is an aggressive yet strikingly beautiful fish species. Named after the famous boxer, Jack Dempsey, these cichlids can grow up to 25 cm (10 inches) in length. For this reason, a large tank is essential - at least 100 US gallons (378 liters or 83 imperial gallons) per adult fish. Since they come from Central America, the water should be slightly alkaline and hard (dGH 18.0 - 30.0 °N ~ 321 - 535 ppm ~ 6.43 - 10.72 mEq), with a pH between 7.0 and 8.5. The ideal temperature is around 25°C (77°F).

The coloration of these cichlids is particularly vibrant when kept in optimal water conditions. Color fading is often a sign of poor water quality or inadequate nutrition. With proper care, they can live over 15 years, although the average lifespan ranges from 8 to 10 years. These cichlids have iridescent speckles and a unique stained-glass appearance on their dorsal fins, which looks especially stunning under the right lighting conditions. Purple aquarium lights can further enhance their natural beauty, but it's best to consult with a store about the ideal lighting.

Tank Setup for Jack Dempsey Cichlids

When housing juvenile Jack Dempseys, it’s essential to choose tankmates of similar size and temperament to avoid aggressive behavior. Never house them with peaceful cichlids, especially African varieties, as they are likely to be harassed. If you keep two or more Jack Dempseys in a small tank (30-40 gallons / 113 - 151 liters / 25 - 33 imperial gallons), dominance issues may arise, with the strongest fish controlling the tank. As they mature (typically reaching 18 cm / 7 inches), ensure ample space. If aggression becomes an issue, consider using a tank divider or rehoming one or more fish. A minimum of 100 US gallons per fish is recommended, though a tank size of 55 US gallons (200 liters, 45.80 imperial gallons) per fish can suffice.

The tank should have plenty of hiding spots, such as caves, rocks, and driftwood, to create a stimulating environment. Males tend to be more aggressive and larger in size.

Avoid using bright lights, as Jack Dempsey Cichlids prefer dim environments. Floating plants like Pistia stratiotes can help reduce lighting intensity, creating a more comfortable environment for them. These cichlids are best suited for experienced aquarists due to their aggressive nature, but with the proper tank setup and compatible tankmates, their behavior can be managed. They can coexist with larger Central American cichlids like Black Belt Cichlids or Midas Cichlids. Be cautious, as smaller fish may be seen as prey.

These cichlids love to dig in the substrate, so planted tanks can be challenging. Most plants will be uprooted, but you can use hardy species like Anubias or Java Fern, which can be attached to decorations and are less appealing to the fish.

Feeding the Jack Dempsey Cichlid

In their natural habitat, Jack Dempsey Cichlids feed on worms, insects, crustaceans, and small fish. While they usually eat eagerly, they may sometimes be hesitant to try new foods. However, with patience, they will eventually accept a varied diet. Their primary food source should be high-quality cichlid pellets, such as Hikari Gold. To ensure a balanced diet, offer live or frozen foods like chopped earthworms, bloodworms, small fish pieces, and chopped mussels. For occasional treats, you can give them crickets, grasshoppers, or fruit flies.

Vegetable matter should also be included in their diet at least once a week. Blanched spinach or peas work well and help maintain their digestive health.

Young fish should be fed three times daily, while adults should be fed at least once a day. Avoid keeping live plants in the tank, as Jack Dempseys tend to eat them. Since they enjoy digging, the gravel layer should be at least 12 cm (5 inches) deep.

Breeding the Jack Dempsey Cichlid

Jack Dempsey Cichlids are commonly bred on a commercial scale, and many hobbyists have successfully raised fry in home aquariums. However, they are not the easiest cichlids to breed due to their aggressive nature, which intensifies during spawning. For this reason, it is best to use a separate breeding tank.

Jack Dempseys reach sexual maturity when they grow to about 7 inches (~18cm) in length. It is difficult to determine their sex when they are juveniles, but as they mature, males develop elongated anal and dorsal fins. Males also tend to show more vibrant coloration and exhibit higher levels of aggression. To ensure you have a breeding pair, it is best to purchase a small group and let them naturally pair off as they mature.

Provide flat rocks in the breeding tank as potential spawning sites. The parent fish will clean the chosen rock in preparation for egg-laying. Eggs may also be laid directly on the substrate, but offering multiple spawning options usually leads to better results. Fertilized eggs will turn an orangey-brown color, while unfertilized or fungus-infected eggs will appear white.

The eggs typically hatch within 3-4 days, and the parent fish are known to be excellent caregivers. They will often dig pits in the substrate to move the fry around the tank for protection. Initially, the fry will consume their yolk sacs, but once this is depleted, they can be fed newly hatched brine shrimp or finely crushed flake food.

An interesting behavior in Jack Dempsey parents is their tendency to partially digest their food and then feed it to the fry, highlighting their strong parental instincts.

After about a month, the fry will be large enough to be moved to a separate grow-out tank, and the breeding pair will likely begin preparing to spawn again.

Special thanks to Kevin, Ben, and Corey Bower for allowing the use of their photographs.

Questions and Answers

The following questions were added here on March 23, 2011, after merging aqua-fish.net/answers with related articles. You are welcome to submit your own questions, but please ensure they are unique and have not already been answered on this page. Use the form at the bottom of this page to ask your question.

• What size tank is recommended for a Jack Dempsey?

  Answer: The minimum recommended tank size for one Jack Dempsey is 55 gallons (208.20 liters, 45.80 Imperial gallons). If you plan to keep more than one, a larger tank will be required.

• What type of fish can I keep with a Jack Dempsey?

  Answer: Many experienced fish keepers suggest housing Jack Dempseys in species-only tanks. However, there are cases where they have peacefully coexisted with Mbuna cichlids. They have also been kept with similarly sized Oscars. That said, it's largely up to the temperament of individual fish. Even after years of cohabitating in a community tank, aggression may develop, and separation might become necessary. When introducing other fish to a Jack Dempsey's tank, proceed with caution and monitor their interactions closely.