2. Never put more than 50 per cent new water in an aquarium 

 containing fish. 



3. Replace evaporation losses with rain water, distilled water, 

 or soft water. 



4. Periodically siphon off all sediment from the tank bottom. 



5. About twice a year, say in early spring and fall, siphon off 

 half of the water and all of the sediment possible. It often pays to 

 remove all plants and animals before siphoning. Replace the water 

 removed with distilled, rain, or soft water, to which one level 

 teaspoonful of sea salt per gallon has been added. The salt replaces 

 exhausted minerals and acts as a tonic. Sea salt, sometimes sold 

 under the name "Turk's Island Salt," can be obtained from pet 

 stores. 



APPENDIX 3 

 Treatment of Diseased Fishes 



Since any hope for the recovery of a diseased fish involves increas- 

 ing its resistance, it should be fed suitable living food if possible. 

 Isolation is desirable, but do not forget that the fish should not be 

 subjected to a sudden change of temperature. Ailing native fishes 

 should be kept at 65° F, exotic fishes at jz°-^^° F, depending upon 

 where the species came from. 



TREATMENT FOR GENERAL ILLNESS 

 One of the most common ailments of wild fishes is a general dis- 

 inclination to eat or move, frequently accompanied by an increased 

 speed of breathing and a caved-in appearance of the belly. An 

 addition of one teaspoonful (level) of common salt and one tea- 

 spoonful of Epsom salts to each gallon of water, followed by an 

 abundant supply of living food, such as daphnia and small earth- 

 worms, will often work a cure. Change the water after a couple 

 of days. If this treatment does not work, place the fish in a tall 

 container and pour in enough table or rock salt to cover the bottom 

 about one quarter inch deep. Watch the fish carefully. As the salt 

 dissolves, the fish will begin to show signs of distress. If it starts 

 to roll over on its back, put it back in fresh water; at any rate, 



[xoi] 



