Pterophyllum species are better known by their common name, Angel Fish. Along with the discus (Symphysodon sp.) it is the most widely kept new world cichlid and has (as the discus) many loyal fans. Part of its popularity is also due to the fact that, since water requirements, temperament and size are comparable to that of the discus, many hobbyists keep them together. The genus Pterophyllum has three species (altum, leopoldi and scalare) which may seem identical to the novice. The hobbyist should seek advice in order to avoid cross breeding. On the other hand, hybrids of P.scalare X P.altum have resulted in fish resistant to fin rot.All species come from South America although from different locations.
P. altum is especially susceptible to Ichthyosporidium infections and should be kept in somewhat higher temperatures (28-30 C) to prevent disease. The fish is territorial and peaceful It shouldn't be kept with very small fish (like neon tetras) since it is going to eat them. Keep an acidic pH (5.8--6.2). P. altum may reach 18 cm while P. scalare will reach a final size of 15 cm. There are many P.scalare morphs available which will satisfy even the most demanding aquarist (marbled angelfish, veiltail angelfish, half-black angelfish etc.). While young the fish can be kept in schools while as adults they form pairs (and they are quite loyal to their pair).