An onshore fish farm in Norway has introduced a new type of filter media to reduce the size of the moving-bed biofilm reactor (MBBR) required in its water treatment process.
Norwegian water treatment company, Sterner, chose Warden Biomedia’s Bioflo filter media for its RAS treatment plant at an onshore fish farm owned by aquaculture specialist, Eidesvik Settesfisk.
Sverre Amrani, technical sales manager at Sterner, said, “Selecting the right media is never an easy task. With Warden’s extensive knowledge of, and expertise in, filter media, we were able to select the most appropriate media for this plant. With their help we have been able to meet our targets.”
The RAS plant comprises two 15m fish breeding tanks, each with a water volume of 780m3, water treatment system, feeding system, energy system for temperature control and a plant for the treatment and handling of sludge. The water treatment system integrates two-step particle separation, an MBBR for removal of total ammoniacal nitrogen and a two-step carbon dioxide removal process.
Warden Biomedia’s Bioflo filter media was chosen because Sterner wanted to reduce the volume of the planned reactor. By replacing the standard biofilm carriers with a higher surface area media, the rate of oxidation of ammoniacal nitrogen into nitrate nitrogen could be increased.
Nitrifying biofilms are thin and the bacteria grow slowly, so the risk of the media clogging up is low. Having a high protected surface area helps ensure high biomass concentrations.
