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Introduction
Behavior
Tank compatibility
Diet
Environment specifics
Blue Jack Dempsey

Introduction

The Jack Dempsey fish is a popular freshwater fish that can be found in aquariums around the world. Jack Dempsey is native to the south Mexican and Honduran regions. The fish can be found in areas of slow-moving waters that are warm and swampy. Water typically appears murky and weedy. Jack Dempseys can be found swimming around the bottom of sandy canals, rivers, and water ditches.

The Jack Dempsey fish was introduced in some parts of Australia, Thailand, and the U.S. (possibly escaping from an aquarium environment).

Behavior

The Jack Dempsey fish is a very popular cichlid, and it’s easy to see why, as they have a striking appearance and notable mannerisms. Like other cichlids, they can be extremely aggressive (named after the boxer Jack Dempsey) and are normally kept with only a few other species, as they’re very territorial in nature. The fish like to keep to themselves and can appear shy (always hiding in caves, rocks, and sand). The Jack Dempsey can become aggressive to other tank mates, regardless of species, when other fish are close to their territory.

Sexing

Females can be identified by being paler in color, whereas males are more vivid. The fins of a female are more round, whereas the male’s fins are more pointed and long. The male’s face will contain bright/sparkle, covering a large portion of their face. The main body of the male will have more prominent spangles. Females may have some spangling on their bodies but will appear more faded. The female typically has some spangle areas on the face; however, the lower area of the face will be blue in color.

Females can lay upwards of 800 eggs per clutch. Both parents protect the eggs, becoming very aggressive towards other fish during the spawning season.

Tank compatibility

The Jack Dempsey fish is considered an aggressive species and normally won’t do well with other fish breeds. Other fish that could be kept with them need to be larger and robust, such as the larger Oscars or Barbs (depending on the tank temperament).

Diet

The Jack Dempsey fish is carnivorous and should be given high-quality pellets, along with brine shrimp, crickets, ghost shrimp, bloodworm, earthworms along with other live and frozen food.

Environment specifics

They prefer to be in an environment with a slow current, along with soft substrate, i.e., sand. The Jack Dempsey fish needs to have lots of different hiding places, with artificial plants being more beneficial than live plants, unless the live plant roots itself into the decorations, like the Java Fern.

This fish needs to be in high-quality freshwater to thrive. In order to promote a high quality of water, frequent water changes along with a good filtration system.

They will live in pH levels of between 7.0 to 8.0, and a dH range of 9 to 20. They will live in water temperatures of around 22°C to 30°C (72 to 86 °F).

Blue Jack Dempsey (species variation)

The blue Jack Dempsey is a variation that’s a natural genetic mutation, becoming increasingly more popular in pet stores. The blue jack Dempsey was first named “Rocio otcofasciata”, and has a colored body of vivid pale blue, along with speckled black markings. The blue jack Dempsey is considered less aggressive compared to the regular Jack Dempsey species and are more delicate and smaller in size.