66 WHOLESALE BREEDING 



at a point a little higher than the regular outlet, which is, of course, 

 also screened according to the sizes of fishes contained. Another 

 point is to have a safety factor by not filling to within 3 inches of 

 the top. That is to say the regular drain should be placed at that 

 level. The importance of the danger of flood in a system of this kind 

 cannot be emphasized too strongly, and unless the point is carefully 

 provided for in the beginning, trouble is bound to ensue, and serious 

 trouble. 



An advantage of the tempering pool is that fishes can be kept in it 

 over winter. Fishes bring better prices in the latter part of the win- 

 ter, and one of the serious problems of the wholesaler is how he shall 

 carry a large stock where it will be kept in good condition and will be 

 available. If the spring has a good flow, the tempering pool can be 

 kept comparatively free of ice and fish can be caught as wanted all 

 winter. 



With the use of ground-level ponds the snake, frog, rat and hawk 

 have good chances of enjoying the luxury of feeding upon goldfishes, 

 unless the vigilant breeder adopts effective means of keeping these 

 pests under control. 



As stated in the former chapter, it is advisable to provide shade 

 for the fishes. Acjuatic plants, particularly water-lilies, are to be rec- 

 ommended. Plant life in a clay-bottom pool should be strictly lim- 

 ited to a few species, as some plants once obtaining a foothold can only 

 be eradicated with the greatest difficulty. The plants to be used are 

 Giant Anacharis, Myriophyllum, Cabomba, Ludwigia and Water 

 Cress. All of these are desirable and furthermore find ready sale. 

 Cyperus, such as shown in illustration, may be kept in pots. 



Specially Equipped Breeding Establishment. A more elaborate 

 and considerably more expensive establishment is shown in figure 53, 

 consisting of greenhouse, indoor and outdoor concrete pools and all 

 accessories going to make up a modern commercial fish-breeding plant. 

 The tanks are 26 inches deep on the outside surface and are not sunk 

 into the ground. This avoids the expense of so much excavating and 

 makes a height which ordinarily cannot be scaled by rats, snakes or 

 frogs. Tanks had best be covered by frames of screening, but these 

 will sometimes be warped or placed on carelessly, thereby giving these 

 particular enemies an opportunity. Let us repeat that galvanized 

 screening should be scrubbed with a stiff brush and water before 

 placing over any kind of fish container. The acid-flux used in making 

 galvanized wire is extremely fatal to fishes, and unless precaution is 

 taken, the first rain on new screening will wash the free acid among 

 the fishes and cause \\'holesale deaths. Uniform size of compartments 



