Note
The total ammonia nitrogen (TAN) produced as metabolic waste in rotifer batch culture systems can reach toxic concentrations as un-ionized ammonia (UIA). Sodium hydroxymethanesulfonate has been used to neutralize TAN in hauling and shipping containers for fish, crustaceans, and mollusks. The objective of this study was to determine the efficacy of a sodium hydroxymethanesulfonate product to neutralize ammonia in a rotifer batch culture system. Rotifers Brachionus rotundiformis were stocked at an initial concentration of 80 individuals/mL and were batch-cultured without water exchange for 7 d. We evaluated response variables that included TAN concentration, rotifer production, egg count, and egg: female ratio.