The use of ozone in a high density
recirculation system for rotifers
G.
Suantika, P. Dhert, G. Rombaut, J. Vandenberghe, T. De Wolf, P.
Sorgeloos-2001
Aquaculture, 201(1-2): 35-49
Abstract:
The use of ozone in the effluent treatment of a
closed recirculation system for rotifers resulted in a significant
improvement of rotifer production and water quality. Compared to a control
treatment, the rotifer culture exposed to ozone did not only support a
higher rotifer biomass (16000 vs. 8000 rotifers ml-1), it also
allowed a prolongation of the culture period for 4 days. Compared to a
control treatment, the ammonium levels were reduced by 67%, nitrite levels
by 85% and nitrate levels by 67%. The supplementation of ozone did not
affect pH and dissolved oxygen levels. Besides the positive effect of ozone
to the nitrification process, a better removal of suspended solids was
noticed as well. This resulted in a decreased turbidity and a reduction of
the number of particles in the culture water. The use of ozone also reduced
the number of bacteria in the culture water.
In general terms, it can be stated that
supplementation of ozone in a closed recirculation system for rotifers
considerably improves water quality, ensures stable and longer rotifer
culture periods and controls bacterial proliferation.
(Laboratory of Aquaculture and Artemia Reference Center, Ghent
University, Rozier 44, B-9000 Ghent, Belgium, e-mail: gsuantika@bi.itb.ac.id)