ESTUARINE WATER SYSTEMS AT SOLOMONS, MD. 



105 



THE MAIN SYSTEM 



The main laboratory research building, 

 about an eighth of a mile from the wharf 

 site, is now supplied with sea water by a 

 dual supply and pump system. The 

 pumps are Moyno progressing cavity units 

 manufactured by Robbins and Meyers. 

 These were chosen in an effort to provide 

 an adequate volume of water with a mini- 

 mum of change in pressure and turbulence. 

 No metal comes in contact with the inflow- 

 ing water, and the pumps were specially 

 modified to this end. Each is powered by 

 a 3-horsepower, 230-volt motor, 1750 rpm. 

 The double V-belt drive reduces the pump 

 speed to about 800 rpm. 



The stators of these pumps are rubber. 

 The rotors, usually made of stainless steel, 

 are molded of polyurethane. The pumps 

 are further modified by the fabrication of 

 several other parts of nylon instead of 



stainless steel and by coatings of polyvinyl 

 chloride. The pumps act to entrap succes- 

 sive small volumes of water and push them 

 through the pump with a minimum of tur- 

 bulence, agitation, or pulsation. Since the 

 entire system is guarded against toxicity 

 from metal and is capable of providing a 

 large volume of water at a relatively low 

 pressure, we expect to be able to conduct 

 a wider range of experiments under con- 

 ditions w^iich compare favorably with 

 those in the estuary. 



Our distribution system in the aquarium 

 room consists of a boxlike trough, sus- 

 pended from the ceiling joists on brass 

 rods. This trough (figs. 3 and 4) is made 

 of cypress and is coated on the inside with 

 an epoxy-base clear sealer. The divider 

 strip, running longitudinally in the trough, 

 allows a 2-way flow in the trough. The 

 primary aim of this trough is to combine a 



Figure 2. — Pumproom detail. 



