The Jack Dempsey is a handsome cichlid known from the Papaloapan River in southern Mexico to the Ulaa River in Honduras. Here it tends to inhabit the slow-moving lower reaches of rivers, drainage ditches, and heavily vegetated, swampy areas with warm, murky water. The aquarium should be at least 5ft long and furnished with a soft sand substrate, as these cichlids like to dig. Provide hiding places/visual barriers in the form of driftwood tangles and rocky caves, ensuring that the decor cannot be easily undermined. Robust plants such as Anubias sp. or Java Fern may be cultivated on pieces of wood, providing additional shady spots. Filtration should be efficient with areas of moderate water movement, and some calmer resting areas out of the current. These fish are susceptible to deteriorating water conditions, so small but frequent water changes are a must to help keep nitrate to a minimum. Perhaps, unsurprisingly for a fish named after a heavyweight boxer, Jack Dempsey cichlids become territorially aggressive as they mature. If a pair forms, they will show much hostility towards conspecifics and similar species, and unless the tank is particularly voluminous with a plethora of visual barriers, other fish may need re-homing for their own safety. In spacious quarters, these cichlids can usually be kept alongside tankmates that are too large to be viewed as a snack e.g. large armoured catfish, silver dollars, Tinfoil barbs etc. Always observe carefully and have a means of separating your fish should it become necessary. From a young age, sexing these fish is made easier thanks to a difference in facial colouring - females carry blue markings on their cheeks, whereas the usually larger males are unmarked.