ZOOLOGICAL SOCIETY BULLETIN 



1203 



the water should be saved and strained back. 

 The supply of water may be aerated at times 

 by lifting it with a clean dipper and letting it 

 fall back slowl3^ A sprinkling can will also 

 serve for this purjjose. All vessels and appara- 

 tus used in connection with the aquarium should 

 be perfectly clean, and it is well not to put 

 the hands into the water at all. Assistance in 

 the way of keeping the aquarium clean may be 

 had by introducing a few tadpoles and small 

 newts to act as scavengers, but the latter should 

 be of very small size. 



The bottom of the aquarium should be covered 

 to the depth of a couple of inches, with fine 

 gravel, or clean white sand in which fishes may 

 rub themselves; it is also essential for the root- 

 ing of plants. 



There should not be too much animal life in 

 the aquarium. The fewer and smaller the fishes 

 the less likely is the air in the water to became 

 exhausted. Two or three small goldfishes to 

 each gallon of water is a safe rule to go by, if 

 the aquarium is large. If small the proportion 

 must be reduced. The question the aquarium 

 presents, when it has been supplied with water 

 and plants, is simply, how many fishes or other 

 air consuming creatures can be accommodated 

 in the quantity of water available.'' Overstocking 

 may disturb the balance within an hour. 



It is probably safe to say that a little neglect 

 in the matter of feeding is better for the per- 

 manence of the aquarium than over attention. 

 It must not be presumed that because fishes will 

 live for months without feeding, it is right to 

 treat them in that way. Fishes left without 

 food are simply fishes kept hungry and in a 

 condition of slow starvation, which can only be 

 described as cruelty. When there is a large 

 supply of plants in the aquarium the fishes hold 

 out longer, the very small ones especially get- 

 ting some nourishment from the young shoots 

 of Anacharis and other plants. 



Many aquariists feed every day. carefully re- 

 moving all uneaten food, which soon decays and 

 fouls the water. Wafer food, made of rice 

 flour, and other prepared foods kept by aquaria 

 dealers are safe, and should be supplied at least 

 every other day. Finely crushed vermicelli 

 is also good. Some of the ordinary household 

 cereals are available as goldfish food, but the 

 beginner should experiment with them cautious- 

 ly. Other foods are. however, desirable at 

 times. Once a week, ]jieces of very small earth 

 worms, or bits of fresh beef should be furnished. 

 If they can be given to each fish on the tij) 

 of a broom straw the chances of contaminating 

 the water bv waste food will be lessened. AH 



uneaten food must be picked, dipped, or si- 

 phoned out, or foul water and a disturbance 

 of the delicate balance of the aquarium will be 

 the result. A milky appearance of the water is 

 usually a warning against careless feeding. 

 Nearly all diseases which appear among gold- 

 fishes indicate that the aquarium needs looking 

 after. The unsightly growths of fungus on 

 fishes, caused by the plant parasites, Snprolegnia 

 and Devoca, indicate careless handling of the 

 fishes, or bad conditions prevailing in the aqua- 

 rium. When the conditions are right, diseases 

 are not likely to appear. Too high a tempera- 

 ture favors the growth of fish fungus. 



This disease is hard to deal with and infected 

 fishes should be removed at once and kept by 

 themselves, where, under proper conditions, 

 they may possibly recover. A pinch of salt put 

 in the water with them may arrest the disease, 

 but when in bad condition a teaspoon of salt 

 to each gallon of water will be necessary. If 

 other fishes are obtainable, it is just as well 

 to kill diseased specimens, since the fungus 

 jH-netrates deeply into the flesh and can not 

 be destroyed if the growth is far advanced. 

 Animal parasites on fishes should be picked off 

 after the fish has been carefully lifted in the 

 dip net. 



One of the first indications of trouble in the 

 aquarium is the presence of the fislu-s ,it the 

 surface with their mouths out of the water, 

 showing that they are suffering for lack of air. 

 The water may be dipped up and allowed to 

 fall back slowly, but the relief afforded will be 

 merely temporary. The temperature of the 

 aquarium should be observed and some of the 

 fishes removed. It may be necessarv to in- 

 crease the quantity of plant-life or stimulate 

 its growth by admitting more light. If the 

 weather is not cold and the window can be 

 opened, air blowing across the surface of the 

 water will be helpful since it may only be 

 necessary to aerate the water and lower the 

 temperature somewhat. There mav be refuse 

 at the bottom which should, of course, be re- 

 moved. 



In taking care of the aquarium, a few, simple 

 implements, such as a half-inch rubber tube 

 for siphoning out the water, a glass "dip tube" 

 for removing small particles of dirt from the 

 bottom, a shallow dip net of cheesecloth for 

 lifting fishes, and a cloth-covered pad (n- rubber 

 scraper with a long handle for cleaning the 

 glass, will be necessary. The dip tube is op- 

 erated by closing the top opening with "the 

 finger to admit or exclude the water as desired. 

 A pair of long wooden forceps and a slim 



