Jack Dempsey


The Jack Dempsey is a popular freshwater fish that originates in the murky warm waters of Central America. It has a base color of dark brown to gray, and displays many iridescent blue and green spots, giving this fish a spectacular look. When breeding, these colors will intensify. The dorsal fin is lined in red, and the female's overall coloration is subdued compared to the male.

The Jack Dempsey requires an aquarium of at least 50-gallons, with a fine sand bottom. There should be rocks and roots for them to hide among. The plants should be hardy as the Jack Dempsey will burrow around and attack them. The aquarium should be divided into territories using hardy plants, if possible. They are territorial and will eat smaller fish that they can swallow.

It is difficult to distinguish between the male and female Jack Dempsey. The females are less brightly colored and usually smaller then the males. Neutral water with soft to medium hardness, a pH of approximately 7.0, and temperatures of 78-82°F is recommended. Jack Dempsey's are open breeders that need well-oxygenated water. They spawn in burrows, laying up to 500 eggs. The fry are well protected by the parents, and once mated, they will continue to spawn once the fry have grown.

Jack Dempsey is carnivorous and will eat most prepared and frozen foods, including freeze-dried bloodworms, tubifex, and ocean plankton, as well as live fish.

{ 2 comments… read them below or add one }

Juan Venegas June 5, 2011 at 2:42 am

I have Jack Dempsey that is about 2′ long, VERY AGGRESSIVE, he has Two Tiger Oscars and Two Convicts as tank mates, but always picks at them, even the larger Oscars which are about 3′ and find it hard to mate with other fish!

Thomas Neil June 28, 2011 at 7:42 am

I have a JD that I have had since he was about an inch long, after several years he is now nudging on 7 inches. After reading the many, many other descriptions of this fish’s personality I was expecting him to grow into a real pugnacious fish with attitude! However this has not been the case with my particular individual.

He is in fact a very tame fish, he lives in a fully planted tank that he shares his with a school of columbian tetras and a bristlenose pleco, the most aggression I ever see him display is when the pleco ventures into his cave, and even then it’s only a very brief nudge and its over. He hasn’t eaten a single one of the tetras, whether this is because they are too fast for him or that he has grown up with them and doesn’t see them as food I’m not sure, but the tetras have even managed to successfully breed whilst in this set up.

I feel as though I definitely have a bit of an unusual JD on my hands, but I guess it just goes to show that every single fish can develop its own personality and not necessarily conform to the ‘stereotype’ each particular breed is subject too.

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