Red devil cichlids appeal to a very specific type of fish hobbyist. There are several species sold under this name, but they all have certain things in common. They are large, colorful, aggressive and have tons of personality. They take skill to keep, if only to accommodate this fish's size and aggression.
All species of red devil cichlids reach about a foot at adulthood. This means they need a large aquarium. A single specimen requires a tank of at least seventy-five gallons. If you want to keep these fish in an "aggressive community" style aquarium, with other large cichlids that can hold their own, they need a tank of at least 125 gallons. When setting up the tank, include visual barriers, things like rocks, plants and driftwood to give fish places to hide from each other. This helps limit aggression. Since red devils love to dig, avoid live plants.
Red devil cichlids have some leeway in terms of specific water chemistry. They can live across a wide pH range of 6.0 to 8.0. As tropical fish, they require water between 70 and 85 degrees Fahrenheit. However, since it is a large, potentially messy fish, they need plenty of maintenance to keep their tank clean. Keep up on water changes to keep these fish healthy. While they are not particular about water pH and hardness, they do need clean water.
Red devil cichlids will eat just about anything. But you still need to make sure they are getting their nutritional requirements. Pet shops sell prepared pellet foods for large cichlids, since flakes are too small. You can also include treats from the grocery store. Red devils will eat veggies like spinach, which provide important nutrients. They also relish animal foods, like earthworms and shelled prawns. However, do not feed a red devil red meat. It has too much fat for fish to digest properly.
Any tank mate for a red devil are a dicey proposition. The only good tank mates are large, hardy fish that can hold their own. Other large central American cichlids can share a tank with some luck. It's important to design the tank with this in mind. Hiding places, and visual barriers to break up the tank can help fish form territories and mitigate aggression. Avoid keeping more than two red devils in the same tank. And even then, only keep a male-female pair, as this fish is particularly aggressive towards members of its own species.