FISH CULTURE. 



921 



and is most convenient for changing the fish from one pond to another. It is not necessary 

 that the ponds should be in a straight line. Where the location demands it, they may be 

 turned so as to lie in a direction nearly or quite parallel with one another. This is easily 

 done by bending the raceways, and lengthening them if necessary, only a curved raceway is 

 sometimes not so convenient as if it were straight. The sides of the ponds may be walled up 

 with stones, laid without mortar, unless the soil is very sandy. Wood may be better for the 

 sides and bottoms, but we are inclined to think is not worth its expense. If the sides of the 

 ponds are laid up with mortar, let it dry thoroughly before letting the water in; then let the 

 water run through it two or three weeks, or long enough to purify the pond before putting 

 any fish in it. It is as well to test it by putting in only a few fish at first; if the pond is not 

 thoroughly purified, the fish in it will turn blind. Ponds should not be built where much 

 surface drainage will run into them ; if they are so exposed, the surface water should be 

 carried off by a ditch around them. The second and third ponds should receive an additional 

 supply of water. If the supply of water is small, it is best to have as much fall between the 

 ponds as the nature of the ground will allow. This fall aerates the water, and makes it as 

 good as new. 



HATCHING HOUSE, NURSERY, AND POND. 



Shape Of Ponds. Where the supply of water is large, it matters very little about 

 the shape of the ponds. The best shape we believe to be the pear shape, such a shape com 

 bining an equable flow of water in all directions, and the greatest amount of surface with the 

 least difference in the temperature of the water. If the nature of the ground demands other 

 shapes, the ponds should be made long, narrow, and deep, rather than broad and shallow. 

 The depth of the first pond should be 2 feet, the second 4 feet, and the third 5 feet. These 

 depths will answer for any size of ponds. It is better for any one wishing to raise a large 

 number of fish, to have several series of ponds, than to attempt raising a larger number by 

 increasing the size of the ponds. Fish do not feed so well in large ponds, are not so easily 

 taken care of, and eat each other more. 



