Jack Dempsey care guide
Jack Dempsey (Rocio octofasciata) — minimum tank 300 L, temperature 22-28 °C, pH 6.5-8.
Compiled by Aquairi from published sources · Published · Updated
Overview
The Jack Dempsey (Rocio octofasciata) is a robust Central American cichlid named after the famous American boxer for its aggressive temperament. Adults develop a stout dark body covered with iridescent blue, green and gold scaling, especially in males.
Taxonomy
- Family: Cichlidae
- Genus: Rocio
- Scientific name: Rocio octofasciata
- Common synonyms: Electric Blue Jack Dempsey
Habitat
Native to slow waters of the Atlantic drainage of southern Mexico, Belize, Guatemala and Honduras. Occurs in warm, weedy canals, swamps and lake margins with soft substrates and abundant cover.
Tank requirements
- Minimum tank volume: 300 L (79.3 US gal)
- Adult size: 20-25 cm
- Temperature: 22-28 °C (72-82 °F)
- pH: 6.5-8
- GH: 5-18 °dGH
- Water flow: moderate
- Lifespan: 8-15 years
Diet
A carnivore in the wild that takes small fishes, crustaceans, worms and insect larvae. In captivity it accepts quality cichlid pellets, frozen and live foods (mysis, krill, earthworm, chopped mussel); avoid mammalian fats and feeder fish.
Compatibility
Territorial and predatory; will eat smaller tank mates and chase or kill weaker competitors. Suitable only for very large set-ups with other robust Central American cichlids — Firemouth, Salvini, Convict, large Pleco. Not a community-tank fish.
Breeding
A substrate spawner. Pairs spawn on a flat rock or pit, lay several hundred eggs and aggressively guard the brood; both parents tend the wrigglers and free-swimming fry for several weeks.
Conservation status
IUCN Red List: Least Concern. The species is widespread in the native Mesoamerican range and feral populations have established in several warm regions worldwide.
Jack Dempsey Breeding Guide
Overview
Rocio octofasciata is a robust Central American cichlid in which males reach around 25 cm. It is a substrate spawner that deposits eggs on a flat hard surface within its territory and provides strong biparental care, with both parents incubating the eggs and guarding the fry once they hatch.
Sexing
Males develop long, pointed tips on the dorsal and anal fins that females lack and tend to be larger. During breeding both sexes darken considerably, appearing almost black with little to no metallic colour.
Conditioning
A compatible, well-fed pair is the foundation for breeding. Maintain water within the species' tolerances; in nature it occupies warm freshwater preferring pH 6-7, hardness around 9-20 dGH and temperatures of 22-30 C, and these ranges guide suitable conditioning conditions.
Breeding Setup
Provide a flat hard surface such as a rock, log or even the aquarium bottom within a defensible territory in a spacious tank. Both parents become extremely aggressive toward other fish during the spawning season, so the pair needs room or carefully chosen, sturdy tankmates.
Spawning Behavior & Trigger
The pair cleans a flat hard surface and the female lays approximately 500-800 eggs per clutch, which both parents then tend. Spawning depends on a stable pair bond and a secured territory rather than a single isolated cue.
Egg & Fry Care
Both parents help incubate the eggs and guard the fry after hatching, and they are known to pre-chew food for the young. If they are stressed or water conditions deteriorate, the parents may consume the fry, so stable conditions and minimal disturbance during early rearing are important.
Common Challenges
Key challenges are the pronounced aggression of a spawning pair toward tankmates and the risk that stressed parents eat their own eggs or fry. A large, calm setup with secure spawning sites and stable water reduces these risks.