Comparing particle removal in RAS farms

Abstract

Particle removal is an important treatment step in recirculating aquaculture system (RAS) for good fish health. This study compares the RAS in MOWI Fjæra and Bremnes Seashore Trovåg to see how well they perform in particle removal. The results showed that both facilities end up with a turbidity around 11 FAU and that they perform evenly both between departments and between each other. The experiment through RAS shows that there’s almost no treatment steps that lowers the turbidity, with an exception of the fixed bed biofilter (FBB) in Trovåg`s hall 1 (H1) department, which gives a 34% reduction in turbidity. With both facilities struggling to decrease the turbidity, it indicates that accumulation of fine particles (<20 μm) is happening and neither of the facilities have effective treatments to avoid this.