A CLOSED CIRCULATING SEA-WATER SYSTEM 



By M. S. Gordon and R. A. Boolootian 



Department of Zoology, University of California, Los Angeles, Calif. 



Abstract. — The closed circulating sea-water system of the Department of Zoology, 

 University of California at Los Angeles, is described, and some parts are illustrated. 

 Some important changes which would improve system operation are listed. These in- 

 clude changes in construction materials for large water tanks and sea-water return lines, 

 and changes in the types of pumps. 



The Life Sciences Building of the Uni- 

 versity of California at Los Angeles con- 

 tains a large, closed circulating sea-water 

 system which is used for both research and 

 teaching purposes. This system has a ca- 

 pacity of about 25,000 gallons of sea water 

 and has functioned very successfully since 

 the fall of 1958. A wide variety of ma- 

 rine vertebrates and invertebrates have 

 been maintained in the system for long 

 periods. 



STRUCTURE OF THE SYSTEM 



The system extends through six floors 

 of the Life Sciences Building. A base- 

 ment room of the building contains two 

 concrete storage tanks of about 9,500- 

 gallon capacity each, two 1,300-gallon ca- 

 pacity sand gravity filters in redwood 

 tanks, an 1,800-gallon redwood supply 

 tank, associated hard-rubber and poly- 

 vinyl-chloride (PVC) unplasticized plas- 

 tic piping, and several pumps (see figs. 1 

 and 2) . From this basement room the sea 

 water is pumped through a hard-rubber 

 pipe to two 750-gallon capacity redwood 

 gravity tanks on the fifth floor of the 

 building (fig. 3). The water then circu- 

 lates by gravity flow through hard-rubber 

 and PVC plastic pipes to 3 aquarium 

 rooms and 10 sea-water tables in various 

 classrooms in different parts of the build- 



ing. From these aquarium rooms and sea- 

 water tables (fig. 4) the water returns to 

 the storage tanks in the basement through 

 Transite pipes. 



The water is pumped from the main 

 storage tank in use (one of the two storage 

 tanks is used at a time, the other being 

 kept as a reserve supply of sea water) into 

 the two filter tanks by means of one of 

 two small, neoprene- rubber-lined cast- 

 iron centrifugal pumps (3-horsepower 

 electric motors, Galigher Vacseal pumps, 

 li/^-inch diameter outlet; fig. 2, A, B). 

 From the filter tanks the water siphons 

 into the central supply tank (fig. 1, E), 

 from which it is pumped by a large sup- 

 ply pump (fig. 2, C) to the gravity feed 

 tanks on the fifth floor. The head against 

 which the main supply pumps operate is 

 approximately 95 feet. There are two 

 main pumps, but only one operates at a 

 time, the second being kept in reserve. 

 Both main pumps are powered by 10- 

 horsepower electric motors and are cast- 

 iron centrifugal pumps lined with high 

 carbon content neoprene rubber (Gali- 

 gher Vacseal, 2-inch diameter outlet). 

 The pumps were originally designed for 

 use as slurry pumps in mining operations. 



All pipes and fittings in the supply part, 

 of the system are fabricated either of hard 

 rubber or of unplasticized PVC. All 



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