Water quality and phytoplankton stability in response to application frequency of bioaugmentation agent in shrimp ponds.

Abstract Splitting the recommended weekly dosage of bioaugmentation agent and applied at varying frequencies were tested to determine its effects on water quality and phytoplankton stability in tiger shrimp ( Penaeus monodon ) grow-out ponds. The supplier's recommended weekly dosage was followed but at varying application frequencies namely: once per week, twice per week, and four times per week for the duration of 120 culture days. A treatment with no bioaugmentation was added as control. Results showed that ammonia and particulate organic matter levels were significantly lower and plankton die-off was greatly minimized if the product was applied four times a week application compared with twice a week and weekly applications. Significant reduction in the number of luminous Vibrio species was observed in ponds with more frequent applications than those with less. For shrimp, survival and production were significantly higher in ponds with twice and four times per week applications compared to the weekly application and the control ( P