You have probably heard the name of some of the most commonly kept cichlids, such as Jack Dempsey (Archocentrus octofasciatum), Oscar (Astronotus ocellatus) and freshwater Angelfish (Pterophyllum scalare). Cichlids are much bellowed fishes kept by devoted aquarists all over the world. Many aquarists set up special cichlid aquariums where they keep cichlids from a certain biotope. Some cichlids are very difficult to care for, while others can be recommended even to beginner aquarists instead of the humdrum Neon tetras and Guppies.
The cichlid family Cichlidae is a huge family containing over 100 genera and a myriad of different species. It is believed to grow even larger in the future, since cichlids are known to inhabit bodies of water that have only been marginally investigated by science. The most notable example of this is probably the Great Rift Valley Lake region in Africa where each lake has its own particular flora and fauna and display a remarkably high amount of endemic cichlid species. These lakes are far from thoroughly researched and their ecosystems are under constant stress due to pollution, over fishing and the introduction of invasive species. Numerous cichlid species may very well become extinct here before anyone even knows that they exist.
Cichlids live in Asia, Africa, South America and the southern parts of North America (below 30 degrees North). They have developed to fit into a wide range of ecological niches and come in all sizes and shapes. This also means that regardless of your level of experience and the type of tropical aquarium you like to keep, there is usually one or several suitable cichlid species for you. A warning should however be issued regarding Dwarf cichlids. Beginner aquarists usually have small aquariums which make it tempting to pick some of these miniature cichlids. Dwarf cichlids are however more sensible to poor water conditions than larger cichlids and therefore an unsuitable choice for beginners. Also keep in mind that it is much harder to keep the water quality up and stable in a small aquarium than in a big one. If you are a beginner aquarist with a small aquarium, it is much better to choose medium sized cichlids. Avoid getting extraordinarily aggressive species and keep the number of cichlids down to avoid crowding.
As mentioned above, cichlids come in all sizes and shapes. They do however share a few notable similarities. All cichlids have teeth in the lower and upper jaws, as well as inside the throat. Just like damselfish, cichlids have one single nostril instead of two. All of the Cichlids are also similar to each other in that they have a smaller intestine leaving at the left side of the body. Normally, the small intestine leaves the body on the right side in fish anatomy.
Since cichlids come from different parts of the world, have different sizes and shapes, display notable differences in temperament, can be herbivore, omnivore or carnivore, and utilize a wide range of dissimilar reproductive techniques, it is naturally impossible to provide any general guidelines that will be true for all cichlids. Before you get a cichlid, you should always investigate that particular species to find out more about how to care for it and make it thrive.