A float-stopper mechanism was designed to drain fish holding tanks directly from the bottom. Unlike traditional, top-drawn standpipe systems, it allows continuous flushing of settled solid waste. It also prevents the accumulation of these wastes between the two standpipes that are used in bottom-drawn, double-walled standpipe systems. When suspended solids are forced upward between the outer and inner standpipes of such systems, a minimum velocity must be maintained to prevent sediment accumulation. This minimum velocity determines the minimum flow rate through the tank. The system described in this report flushes well over a wide range of flow rates.
Hagopian, D. S. and Riley, John G., "A Low-Flow Self-Cleaning Drainage System for Fish Rearing Tanks" (1998). Marine Sciences Faculty Scholarship. 3.
Hagopian DS, Riley JG. A Low-Flow Self-Cleaning Drainage System for Fish Rearing Tanks. Progressive Fish-Culturist. 1998;60(2): 152-155.
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