APPLICATION OF ION EXCHANGE AS BIOFILTER FOR COMPLETE RECIRCULATlON IN AQUACULTURE
A recently developed system for recirculation of aquaculture waste water was examinined. It is based upon the use of settling, a mixture of 3 ion exchangers, and sand filtration. The results were satisfactory, giving an acceptable water quality over a period of 7 months with complete recirculation. The ion exchange unit is also operating as a biobed. The overall efficiency of the biobed and the combined ion exchanger is very acceptable and the capacity (defined as total removal between two elutions) was significantly higher than by pure ion exchange, which makes it attractive to use these moderately priced ion exchangers. Simul-taneously it is a great advantage that the ion exchanger, during the entire cycle, can remove ammonia as well as organic pollutants immediately, independent of possible fluctuations in the biological activity. “Complete abstract not presented.”