Submitted to: University of Arkansas-Pine Bluff Aquaculture Field Day
Publication Type: Abstract only
Publication Acceptance Date: 10/6/2004
Publication Date: 10/7/2004
Citation: Ludwig, G.M., Hobbs, M.S., Perschbaucher, P. 2004. Control of ph in sunshine bass fingerling production ponds [abstract]. Book of Abstracts University of Arkansas-Pine Bluff Aquaculture Field Day. p. 51. Interpretive Summary:
Technical Abstract: Sunshine bass fingerling production ponds often develop high pH just at the time of stocking 5-day-old fry. The levels often are lethal to the fry. Unionized ammonia levels may also reach unhealthy concentrations. An experiment was performed that compared the effect of using sodium bicarbonate at 56 kg/ha or eliminating the use of inorganic fertilizers on pH and other water chemistry variables and on concentrations of chlorophyll a, phytoplankton, primary productivity, and zooplankton during 12 days after ponds were filled and fertilized. Control ponds (0.04 ha) were fertilized with organic and inorganic fertilizers at recommended amounts. Sodium bicarbonate use resulted in a nominally lower pH on all days of the experiment; however ponds that only received organic fertilizer had pH values significantly lower than the other treatments 75% of the days. Chlorophyll a, TAN and un-ionized ammonia concentrations were also significantly lowest in organic-only fertilized ponds on most days and well below sunshine bass fry tolerance limits. For most water chemistry variables tested, sodium bicarbonate resulted in a slight but not statistically significant (at p=0.05) improvement while use of organic fertilizer significantly improved water quality. The zooplankton food base for sunshine bass fry were not significantly different in the treatments. That suggests using lower amounts of fertilizer in older ponds would be safer for sunshine bass fingerling culture.