AMATEUR FISH CULTURE 



action of the running water for a couple of months 

 at least before any ova or fry are introduced. 



Another plan, and a simpler and less expensive 

 one, is to face only the ends of the ponds with 

 brick and cement work, carrying the brickwork 

 into the earth on each side, as shown in Fig. 1. 

 In this case the sides of the ponds should be 

 slightly sloped as shown in Figs. 2 and 3. It is 

 advisable if possible to make the outlet at the 

 level of the bottom of the pond, if the pond is 

 lined with cement, but if the pond is only 

 cemented at the ends, it is better to have one in 

 mid- water or even near the surface. As I have 

 said before however, an outlet should be made at 

 the level lowest part of the bottom, so as to 

 facilitate the emptying of the pond. The pond 

 should however be made shallower at the lower 

 end. Fig. 2 shows a section of the upper end, 

 and Fig. 3 of the lower end of such a pond. 



The open trough between ponds in a series 

 should be at least three yards in length, but it is 

 better if not straight. Stones and gravel should 

 be put in these troughs in order to make the 

 water as rough as possible, and if some fresh- 

 water shrimps can be introduced so much the 

 better. 



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