GOLDFISH 



449 



a stick will be effective. Sediment may be removed by a glass dip 

 tube or rubber siphon. 



A 5-gallon aquarium is the minimum size recommended, but when 

 it is possible a larger vessel should be used. A tank 24 inches long, 

 12 inches wide, and 15 inches high, with a capacity of 18 gallons, 

 makes a suitable aquarium for a parlor or living room. A receptacle 

 of that size should maintain 5 two-inch fish of different types and 

 varieties, 2 tadpoles, and 10 snails. When larger aquaria are used, 

 the number of fishes, scavengers, and plants may be increased pro- 

 portionately. If the fish are larger, their number should be corre- 

 spondingly reduced. A good rule in 

 stocking an aquarium is to allow 1 

 gallon of water to each one-half inch 

 of fish. Maintenance of goldfish 

 under conditions less favorable than 

 these is possible by making frequent 

 changes of water. 



LIGHT 



The aquarium should have a 

 northeastern exposure in summer, 

 but in winter it is advisable to so 

 locate it that it will get the sunlight 

 two or three hours a day. The light 

 should enter an aquarium in about 

 the same way it enters a stream — 

 from the surface of the water. Too 

 much light will overstimulate the 

 growth of algae, causing the water to 

 turn green. 



WATER 



The best water supply for an 

 aquarium is nearly always from a 

 river, pond, or cistern, as water from 

 such a source conforms more nearly 

 to natural conditions. Excessively 

 hard water, from whatever source, is 

 undesirable. Mineral requirements 

 should be satisfied preferably in the 

 diet rather than by the addition of 

 salts to the water. The demands of 



both fish and plants for inorganic matter are so small that a reason- 

 able amount of natural crustacean food in the diet should be sufficient 

 to maintain the balance. 



Fig. 4. — Floating arrowlicad (Sagifta- 

 ria natans). One-half natural size. 

 A very desirable plant tor the aqua- 

 rium. Flowers above water surface, 

 but fruit ripens on or below the sur- 

 face of the water 



TEaiPERATURE 



The temperature of the water in an indoor aquarium will range, 

 from 50 to 80° F. in Avinter and from 65 to 80^ F. in summer. 

 A temperature somewhat in excess of 85° should not prove harmful 

 if the water is well aerated, but if the fish show signs of distress 



