Can You Mix Tropical Catfish With Cichlids in Aquariums?

You can keep some catfish with some cichlids, but that's a qualified yes. You have bear in mind that both cichlids and catfish can have specialized water chemistry requirements and may have behavioral issues that make them bad roommates. Always research the exact species you want to keep.

  1. Water Chemistry

    • When fish hobbysts say "African cichlids," it's understood to mean cichlids from the Rift Valley in eastern Africa.

      Both cichlids and catfish have wide distributions, including multiple continents. But each species has its own preferred water chemistry, based on the conditions of its home waters. For example, African cichlids and synodontis catfish from the African Great Lakes need hard, alkaline water to survive. But South American cichlids and catfish from the Amazon River need the opposite water chemistry: soft and acidic water with very little in the way of dissolved minerals. You need to make sure fish can survive at the same water parameters before trying to keep them in the same aquarium.

    Fish Size

    • Channel catfish grow longer than a meter.

      Keep in mind that both groups include both huge and tiny fish. For example, dwarf cichlids like apistos only reach a few inches at most. Similarly, Otocinclus catfish -- also called dwarf plecos -- max out at about an inch and a half. Meanwhile, the common pleco can actually grow more than two feet long. The Central American jaguar cichlid reaches a similar size. It's always a great idea to make sure you look up how big your fish get before you purchase them.

    Cichlids Aggression

    • African cichlids are notorious for their aggression, but some species are peaceful.

      Within the aquarium hobby, the cichlid family is notorious for aggression. But it's a huge family of fish, and this varies greatly from species to species. For example, most of the African cichlids will beat up any other fish in the same aquarium and so need robust tank mates that can handle their aggression. On the other end of the spectrum, many river cichlids are peaceful to the point of being pushovers. When selecting tank mates for freshwater angelfish, you actually have to worry about picking fish that will bully these delicate cichlids.

    Catfish Aggression

    • Most pleocs are peaceful, but there are exceptions.

      While not as well-known for aggression, many species of catfish can give cichlids a run for their money in terms of their temper. But again, this varies species to species. For example, most plecos, even the huge common pleco, rarely bother other fish. But a group of plecos called the panaque can be much more brutal. These fish have the same heavily-armored pleco body type and a more aggressive temperament. So while you usually have to worry more about cichlids picking on your catfish, the inverse is true in some situations.