Significantly improved turbidity with Razone

‘We see that the water is clearer and cleaner, and we’re now able to achieve the water quality we desire,’ says Frode Reppe at Vikan Settefisk. Photo: Vikan Settefisk

 

Vikan Settefisk was dissatisfied with the water quality. Now, with the Razone and ozone system from Normex, they see significant improvements: ‘The quality has never been better.’

‘We installed the system because we weren’t satisfied with the water quality. It simply wasn’t good enough, and we needed to take action to reduce turbidity and particles,’ says Frode Reppe of Vikan Settefisk. He runs the company with his partner Britt-Åse Skarsvåg.

Founded in 1986, Vikan Settefisk is a small family-owned business with eight employees. They produce five million salmon smolt per year on Frøya. In 2020, they built a new recirculating aquaculture system (RAS).

Before contacting Normex, Vikan Settefisk had taken several measures to try to improve the water quality.

‘We had previously installed an ozone and protein skimmer at the farm, but it didn’t achieve the desired effect. We later added a sand filter, which improved the water quality somewhat, but it still wasn’t enough. It was particularly the particles in the water that we were unhappy with.’

Razone is a unique solution for cleaning and clearing water in fish farms on land. Photo: Normex

Improving water quality and fish welfare

The Razone system from Normex was installed last September at the RAS farm. These farms, ensures that 99 percent of the water is reused. This leads to low water consumption but, in turn, requires water treatment to prevent bacteria and particles from accumulating.

Michael Vadseth, Sales Manager at Normex, explains that Razone solves these issues by effectively removing microorganisms, microparticles, and contaminants from the water.

‘The small particles that are not captured by mechanical and biological filters, will accumulate throughout the production period. These are removed by the Razone system, ensuring good, stable water quality throughout the period.’

Normex has also increased the ozone capacity at the farm by adding an additional ozone generator and has created a shared control system and ozone distribution across all departments. The ozone system binds and micro-flocculates the small particles, allowing them to be effectively removed in the Razone system.

‘Ozone treatment also has a positive effect on water colour and microorganisms,’ he elaborates.

 

Michael Vadseth, Sales Manager at Normex. Photo: Normex

 

Partial stream treatment yields results

Vadseth says the results have been remarkable since the installation:

‘After we installed the Razone system at the farm, turbidity has dropped to very low levels – and this with a partial stream treatment of 12 per cent.’

The turbidity in the department where Normex installed Razone is now 1 NTU, which is a significant improvement from Vikan Settefisk’s previous measurements.

Test results from Nemko Norlab on SS, colour, and bacterial counts show the same positive development.

Reppe at Vikan Settefisk also reports clear improvements:

‘The water quality is now better than ever. We see that the water is clearer and cleaner, and we’re now able to achieve the water quality we desire.’

 

‘The service is exceptional!’

The Normex delivery also includes an online management system, where water quality and operational parameters are continuously monitored for optimal operation. It is accessible to and can by adjusted by both Vikan Settefisk on site and Normex virtually.

Reppe says he is extremely satisfied with the service level from Normex:

‘The service is exceptional! Bjørn Monsen (Technical Manager at Normex, editor’s note) is a real expert and knows what he’s talking about. If we have issues, we call Bjørn. It might be three times a day or once a month.’