CHAPTER VII. 



ADULT TROUT. 



SUPPLY OF WATER FOR GIVEN NUMBER OF TROUT. 

 This has never been accurately determined, and we do 

 not know that any general rule can be given applicable 

 to all times and places. The quantity required for any 

 given number depends very much upon the temperature 

 of the water, a certain supply in cold weather sustaining 

 many more in good condition than the same supply in 

 hot weather. It is the same with trout as with mankind. 

 If many people are packed together in a close room, they 

 will soon begin to suffer ; but will not feel the bad effects 

 so soon in cold weather as in warm. Now the water 

 contains the air upon which the trout lives, and the 

 amount requisite depends upon the amount of air which 

 is in the water. A still and smoothly flowing stream, 

 with little vegetation in it, contains the least amount of 

 air. Hence the value of a fall of water between the ponds 

 if the stream is small. The volume of water required 

 depends also upon the shape of the ponds and upon the 

 size of the fish. We can only say about what quantity is 

 necessary and leave each owner of ponds to obseive for 

 himself whether more or less fish do well with it. 



It must always be borne in mind that the larger the 

 supply of water the better for the trout ; and the trout- 

 breeder on a large scale will find better success with 

 small ponds and large supply than in any other way. 

 For ten thousand fish the stream should not be less than 

 seven inches square (that is, forty-nine square inches) 

 and would be still better if it was seventy-five square 

 inches. A less supply will perhaps do ; but with it there 

 is danger of disease and death to the fish. We will say 



