Zeolite filters - tools to improve water quality in recirculating systems in aquaculture

For the efficient and sustainable use of water in recirculating aquaculture systems, in order to improve water quality, zeolite filters have been used by retaining ammonia. The efficiency of the filters was tested in systems with volumes of 220 liters of water, populated with batches of 36 carp seedlings (Cyprinus carpio) in summer I. Horizontal filters with zeolite bed and composite filters, obtained from a granular mixture of silicate glass and zeolite, were used when filtering the water. For the determination of ammoniacal nitrogen, the continuous concentration criterion (CCC) and the maximum concentration criterion (CMC) were used. After 24 and 48 hours of water filtration using clinoptilolite filters, it was found that the maximum permissible values of ammonia in the water were not exceeded. Ammonia is absorbed in relatively large quantity, zeolite improves the filtration yield, which recommends the use of these types of filters in controlled recirculating systems in aquaculture.