AQUARIUM MANAGEMENT 



13 



Sick Fishes. It is always safer to remove an affected fish from 

 its fellows. If the trouble is a contagious one, the aquarium or tank 

 should be thoroughly disinfected, not overlooking the plants in this 

 matter. For all practical purposes they can be sterilized by placing 

 for one hour in a permanganate of potassium solution, 3 grains by 

 weight to the gallon of water. Satisfactory results will also be given 

 by dipping plants for a few moments in concentrated lime water, or 

 in household ammonia, reduced to one-twentieth strength. Either of 

 these methods should be applied to all new plants introduced into the 

 aquarium, especially those collected from the wild, or from aquaria of 

 doubtful condition. In case of an aquarium becoming contaminated, 

 it can be disinfected by dissolving in it permanganate of potash to the 

 strength already indicated, allowing it to stand from two to three 

 hours, first removing all mussels, snails and fishes. In changing to 

 clear water again it will do no harm if a little permanganate remains. 



Unless newly acquired fishes come from a source beyond sus- 

 picion it is a grave risk to introduce them at once into an established 

 aquarium of healthy fish. They should first be quarantined and care- 

 fully observed for about two weeks, this being particularly true of 

 imported goldfishes. They may already be inoculated with diseases 

 only in process of incubation, but which will nevertheless develop. 



Scavengers. Nature has supplied us with means of getting rid 

 of most of the harmful offal and decomposition in the aquarium. 

 These consist largely of those species of snails that do not attack the 

 plants. Among the best known, most satisfactory and easily obtained 

 are the large Japanese Snails (Viviparus malkatiis), the so-called 

 African Paper-shelled Snail (Lyinnaca anriculavia) , the Ramshorn Snail 

 (Planorbis), and the Pond Snail (Physa). These are all active in eat- 



FiG. 4. African Fic. 5. Red Ramshorn Fig. 6. Japanese 



Tun BrsT Freshwater Aquarium Snails (Life si.-:e) 



