water fishes, which make such a splendid showing, should be kept at 

 about 70° to 75° F., while trout and kindred varieties do best at 

 45° to 55° F, This requires warming the water in the winter and re- 

 frigerating it in the summer. 



Aquatic plants are not only essential in aquariums but they im- 

 prove the scenic effect. Fish throw off carbonic gas and plants 

 absorb it. Among the aquatic plants best suited to fresh water 

 aquariums are Cabomba, Potamogeton, dwarf Sagittaria, Anacharis, 

 and Myriophyllum. Some species of the last named probably are 

 preferable. For salt water aquariums Irish moss, red and green 

 algse and sea lettuce are excellent aquatic plants; some aquariists 

 consider the latter the best. 



Fishes suffer from maladies, both parasitic and non-parasitic. 

 If they become infected with parasites, either internal or external, 

 it is advisable to do away with them or at least segregate the infected 

 ones for observation and treatment, though there is really not much 

 that can be done for them. In the case of non-parasitic troubles, salt 

 water baths have been found very beneficial, the solution in which the 

 fish are temporarily immersed being quite strong. This treatment is 

 considered a specific for vegetable growth or fungus caused by fre- 

 quent or careless handling. 



In displaying fishes care must be taken to see that only com- 

 patible species and sizes are kept in one container. For example, in 

 a salt water aquarium it is not safe to put certain other species with 

 angel fish, for the latter are likely to destroy them. Likewise it is 

 folly to put bass and trout together, even though temperatures per- 

 mitted. Most of the fishes ordinarily displayed are cannibalistic. 

 Thus, trout in an aquarium must be of about equal size to avoid loss 

 from this cause. 



Among the salt water fishes which are most interesting to the 

 public may be mentioned the parrot fish, angel fish, squirrel fish, 

 grouper, hind, sea horse, and yellowtail. Pleasing displays of fresh 

 water fishes may be made of such species as salmon, trout, catfish, 

 pike perch, bass, sunfish, muskellunge, goldfish, tench, dace, albino 

 trout, bream, crappie, strawberry bass, whitefish — though hard to 

 keep — ling cod, and eels. Turtles make a most interesting display; 

 frogs also may be shown. Among the salamanders, newts, mud 

 puppies, and hellbenders are of interest and are hardy. Clams and 

 other mollusks are valuable in aquatic displays, but hard to keep. 



A pool or grotto containing seals or large fish is also most inter- 

 esting and instructive in a public aquarium. Fur seals would be of 

 greatest interest, but they are more difficult to secure and to keep 



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