AERATING DEVICE FOR SALT WELL WATER 



167 



stant tower height, when only a low or 

 moderate degree of saturation is desired. 

 As higher degrees of saturation are at- 

 tained, then the aerator becomes increas- 

 ingly tall and spacing increasingly 

 important. 



DEFINITIVE AERATOR 



Since it was desired to use highly 

 saturated water as a medium for skipjack, 

 some extrapolation was done from the 

 upper curves of figures 5 and 6 in planning 

 the definitive aerator. It w^as decided that 

 16 trays spaced at 2-inch intervals would 

 provide near saturation with a moderate 

 pressure requirement, and if these trays 

 were perforated with i/g-inch holes at 1/2- 

 inch intervals there would be sufficient 

 capacity to carry water at flow rates up to 

 about 100 gallons per minute (and per- 

 haps more). A diagram of the aerator 

 ultimately built from these plans is shown 

 in figure 7, from which the following 

 features will be noted. The aerator is 

 essentially a wooden box surmounting a 

 concrete tank which receives the aerated 

 water. The ends of the aerator are slotted 

 for ingress of air, but light is excluded 

 as much as possible to inhibit the growth 

 of algae. Within the box are three rows 

 of 16 long, narrow trays, wdiich can be 

 pulled out like drawers for cleaning or 

 inspection. All construction is of wood 



except for the perforated tray bottoms, 

 which are of pressed fibreboard doubly 

 coated Avith an epoxy resin. The aerator 

 has been in nearly continuous use for 18 

 months with only slight attention being 

 required. Tray cleaning has not been 

 necessary. Water passed through it 

 ranged from 95 to 100 percent saturated 

 with oxygen, and was successfully used for 

 the maintenance of skipjack (see Naka- 

 mura, this collection). 



LITERATURE CITED 



Betz Laboratories, Inc. 



19.57. Betz handbook of industrial water con- 

 ditioning (r)th ed.). Betz Laboratories, 

 Philadelphia. 2.54 pp. 

 McKelvey, Kenneth K., and Maxey Brooke. 



1959. The industrial cooling tower. Elsevier 

 Publishing Co., Amsterdam. 429 pp. 



Xorris, Kenneth S., Frank Brocato, Frank 

 Calandrino, and William N. McFarland. 



1960. A survey of fish transportation methods 

 and equipment. California Fish and Game, 

 vol. 46, No. 1. pp. .5-.33. 



Shaw, Paul A. 

 1936. Hatchery trough aerators. California 

 Fish and Game, vol. 22, No. 2, pp. 126-136. 

 Sverdrup, H. v., Martin W. Johnsoih, and Rich- 

 ard H. Fleming. 

 1942. The oceans ; their physics, chemistry, 

 and general biology. Prentice-Hall, New 

 York. 1087 pp. 

 Tester, Albert L. 



1952. Establishing tuna and other pelagic 

 fishes in ponds and tanks. U.S. Fish and 

 Wildlife Service, Special Scientific Report — 

 Fisheries No. 71. 20 pp. 



