Characterization of solid wastes from sablefish (Anoplopoma fimbria) in intensive culture

Abstract

Sablefish (Anoplopoma fimbria) is a Pacific marine species that adapts well to aquaculture, grows extremely fast, and command a high market price. Because of environmental and regulatory concerns, increased production of this species is likely to occur in land-based systems. Little is known about the waste production characteristics of sablefish, information that will have a critical impact on the design of aeration, solid removal, and biofilter design for this species. It was found that the concentration of total suspended solids (TSS) in the effluent was extremely low and the mean TSS ranged from 0.9 to 1.7 mg/L. Compared to other important culture fish, sablefish produce significantly less fecal solids (5.2–7.9 % based on feed inputs) and less of their solids settled out (57.3–65.8 % of total suspended solids). TSS production following feeding of a special feed for reuse systems was significantly higher (51.9 %) compared to fish fed a conventional diet. The reduced production of TSS by sablefish is due to higher apparent digestibility coefficients and possible production of wastes that are not retained on the standard filter used for TSS analysis. Additional rinsing of the filters to remove salt and the use of large sampling volumes can significantly improve the accuracy of TSS analysis for marine culture species.