34 MAINTAINING FISHES 



dried foods. It is favored by temperatures from TO*' to 

 80° F. It spawns at a weight of two pounds or less but 

 will attain a maximum of 20 pounds or more imder 

 natural conditions. 



Small South American catfishes of the genus Cory- 

 dorus are popular aquarium fishes. They are obtain- 

 able from dealers in tropical fishes. They can be bred 

 in captivity but do not reproduce as readily as many 

 other species of "tropicals." 



Cyprinodontids 



All of the cyprinodontids mentioned here are 

 exotics, live-bearers, widely available, breed readily 

 in captivity, and have been used for experimental 

 work. They require temperatures from 75° to 80° F. 

 and can utilize dried foods but benefit from at least 

 some Hve food such as microcrustaceans. 



Few fishes are more adapted to aquarium condi- 

 tions than the guppy (Laebistes reticulatus) » It re- 

 produces rapidly, and since it is not too inclined to eat 

 its young, no special precautions are needed to insure 

 their survival. It has a short life cycle. Numerous col- 

 ors and finnage mutations of the guppy have been 

 preserved by hobbyists. 



The platy (Platypoecilus maculatus) and sword- 

 tail (Xiphophorus helleri) are quite similar to the 

 guppy in size, color variations and environmental re- 

 quirements but do not reproduce as successfully or 

 survive as weU as guppies. 



Percoids 



The green sunfish (Lepomis cyanellus) occurs 

 throughout most of the eastern United States. It is 



