Red terror cichlid or harlequin cichlid (lat. Cichlasoma festae) is a bright, large and territory dependent fish of Cichlidae family. Often the fish is kept in species tanks due to its temper. This fish is moderately difficult in terms of keeping. But this is one of the best fishes for those who want to have extremely clever, large, bright and aggressive fish in a tank.
The keyhole cichlid (lat. Cleithracara maronii) is a very nice, but not very popular tank fish. Most of pet shops and breeders ignore it because of its timidity and not very bright coloring and this is a big mistake. Since this is a peaceful, clever, good-tempered fish unlike the majority of other cichlid species, which are brighter, but much more aggressive.
When you buy a young Salvin’s cichlid (lat. Trichromis salvini) it doesn’t look very attractive. But things change when the fish grows up. It becomes a very bright and good looking fish, it is quite noticeable in a tank and it draws the eye. Just like all cichlid species it can be quite aggressive, since this is a territory dependent fish. Also it is a predator, so it’ll treat all small sized fishes as food. Therefore it should be kept separately from others or with other species.
The Texas cichlid (Herichthys cyanoguttatus, ex. Cichlasoma cyanoguttatum) is a large, good looking and at that rather aggressive fish. In the wild it inhabits in rivers of Texas (for example, Rio Grande, due to which the fish got its name Rio Grande cichlid) and in North Mexico.