Trout Breeding. 145 



do hot reduce the temperature more than ten degrees 

 or you may have either dead or barren fish in your 

 ponds. The aeration of water, as before described, is 

 like pumping air to the submarine diver — it means life. 



Large fish should not be sent in circular tanks, be- 

 cause they will crowd to the side, which closes one gill 

 cover and prevents the other from closing; hence they 

 cannot breathe well and may soon die. 



Twenty pounds of trout will live four hours in 

 twelve gallons of water if under 40° Fahr. Two 

 pounds of trout will live for four hours in three gal- 

 lons at 40®. 



