Selection of aerators for intensive aquacultural pond

Aeration cost is the third largest cost in intensive aquaculture system after post larvae and feed cost representing about 15% of total production cost. Therefore, selection of aerators plays a major role in maximizing the profit in such system. Over the years, various types of aerators have been developed specifically to enhance the production of aquatic species. The performances of these aerators are generally compared in terms of standard aeration efficiency. However, suitability of a particular aerator at different pond sizes and water quality conditions can best be determined in terms of aeration cost per unit time of operation. In the present study, economic performance of five different aeration systems circular stepped cascade (CSC), pooled circular stepped cascade (PCSC), 1-hp paddle wheel, 2-hp paddle wheel and propeller aspirator pump were evaluated and compared at different pond sizes, initial DO concentrations of pond and operating hours of aerators; assuming a typical Indian major carp (IMC) culture with commonly practiced stocking density and feeding. Both CSC and PCSC aerators were found to be suitable for pond size less than 1000 m(3). However, for pond sizes more than 5000 m(3), 1-hp paddle wheel and 2-hp paddle wheel aerators were found to be efficient. (C) 2013 Elsevier B.V. All rights reserved.