NOTES FROM THE AQUARIUM 



OF THE MARINE LABORATORY, ABERDEEN 



By H. J. Thomas 



Department of Agriculture and Fisheries For Scotland, Marine Laboratory, Aberdeen, Scotland 



Abstract. — The closed circulation system described comprises twin reservoir tanks, 

 service tank, header tank, display tanks, and filter bed. Special features include con- 

 struction in water-tightened concrete with vulcanite-lined cast-iron or alkathene tubing, 

 reservoir tank capacity five times that of the display tanks, aerator pump which is water 

 sealed, and the use of marble chips in the filter bed. The aquarium is furnished with 

 several levels of temperature control to allow maintenance of the appropriate seasonal 

 sea temperature. Isolation tanks are provided for experiments which might involve 

 risks if undertaken in the main system. 



The Marine Laboratory's aquarium is 

 essentially a research tool, but the basic 

 design, stocking, and temporary decora- 

 tion of the tanks is adapted to afford as 

 high a standard for display as is com- 

 patible with the primary function. 



STRUCTURAL DATA 



The basic layout follows the standard 

 pattern for a closed-circulation sea-water 

 aquarium (figs. 1 and 2). The relevant 

 capacities and ratings of the main aquar- 

 ium installations are as follows : 



Volume of large display 



tanks (9 at 5 by 5 by 5 



feet) 7,000 gallons. 



Volume of small display 



tanks (8 at 3 by 21/2 by 



2y2 feet) 800 gallons. 



Volume of portable tanks 



(as required) 400 gallons. 



Total volume of display 



tanks 8,000 gallons. 



Volume of service tank .500 gallons. 



Volume of header tank 3.50 gallons. 



R e s e r V o i r/sedimenta- 



tion twin tanks, each of 



capacity 40,000 gallons. 



Main circulation pump 



rated capacity 4,000 gallons per 



hour. 

 Filter bed, combined total 



filter area 12 by 16 feet. 



Refrigerator rated capac- 

 ity 60,000 B.t.u. 



Heater capacity 3 kilowatts. 



Reinforced, water-tightened, sulphate- 

 resisting, concrete units are poured in a 

 single operation, thereby avoiding sutures 

 with consequent corrosion of the reinforc- 

 ing by sea water. In the reservoir tanks 

 where single-operation pouring is difficult, 

 the outer reinforced-concrete shell is lined 

 with asphalt, and this in turn is supported 

 by a brick layer internally faced with 

 water-tightened concrete. The reservoir 

 tanks are constructed with a sump to fa- 

 cilitate pumping out. 



Display-tank walls are smoothed, and 

 all corners are rounded. 



One-inch-thick plate-glass fronts to the 

 display tanks are, at their deepest, 4 feet 6 

 inches from the water surface. Glasses 

 are bonded into position with. Glasticon 

 cement of the grade appropriate to the 

 area of the bonding surface, which must 

 be true, and to the depth of the tank. 



The original sea-water piping is of vul- 

 canite-lined cast iron. Extensions and 

 replacements are undertaken using alka- 

 thene (Imperial Chemical Industries — 

 I.C.I. — black polyethylene) . 



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