Razone

Cleans and clears water in fish farms on land

Razone is a unique solution for cleaning and clearing water in fish farms on land. The system is sustainable, and improves water quality and fish welfare.

Levels of organic matter in a recirculation aquaculture system (RAS) are often high. That in turn creates a substantial threat of infections and blooms of harmful microorganisms, microparticles, micropollution and hydrogen sulphide.

Razone overcomes these problems by effectively eliminating microorganisms, microparticles and pollution in the water. Since the system is ozone-based, it operates without the use of hazardous chemicals.

Reduces particulate matter in water

Razone improves and maintains water quality, and contributes to better fish health, biosecurity and fish welfare.

  • Ozone clears the water and improves its quality by removing dissolved organic substances in RAS farms
  • It removes colloidal solids through microflocculation, oxidation and flotation
  • Oxidation with ozone forms microflocculates, making it easier to remove particles
  • A high level of organic substances in RAS farms creates a basis for the growth of toxic nitrates, which are converted to harmless forms by ozone

Improved fish welfare and profitability

Increased biosecurity

Biosecurity in an RAS farm is increased by lowering the risk of micropollution, improving fish welfare and reducing mortality.

Reduced costs

Costs are reduced in an RAS farm through better feed take-up and utilisation. It also improves the effectivity of the daily operations at the fish farm.

Increased growth and profitability

The profitability of an RAS farm increases because better growth conditions for the fish reduces production time.

Razone treats water in a two-stage process

Circulation water to be treated is conducted into a sidestream to Razone’s contact tank, where ozone is added.

The water is then pumped to the flotation tank, where small bubbles are injected. Flocculated particles shoot to the surface, allowing the sludge to be removed from the top and conducted to the sludge tank. Treated water emerges clean and clear from the bottom of the flotation tank, and is conducted back to the RAS farm.

Razone can be used either before or after the biofilter, and functions equally effectively in fresh water or seawater. Its control system automatically regulates the ozone concentration in the water in line with the quality of the latter. The system can also be connected to the farm’s general control system.

Razone can also desinfect pipes and tanks between intakes of fish.

Compact – easy to use

Razone improves water quality – promotes fish health and growth

  • Clears the water
  • Increases biosecurity
  • Reduces the threat of hydrogen sulphide (H2S)
  • Promotes fish health
  • Improves utilisation of fish feed
  • Increases growth
  • Compact
  • Easy to use

Research on improving water quality in RAS farms

We are pursuing a research and development project in collaboration with aquaculture specialist Mowi and Norway’s Nofima food research institute, with support from Innovation Norway.

  • Comparing two (three) broodstock production batches in the same department at Norway’s Mowi Steinsvik, with and without the use of Razone.
  • Preparations and testing carried out in the spring-autumn of 2020 with two (three) batches in the same size category, with comparable density and biomass.

The goal of the project is to determine whether Razone:

  • Reduces particulate matter in water
  • affects water quality
  • affects the health status of the fish

"Never had such good growth"

Growth up 20 per cent

Growth (g) after 60 days with Razone was about the level reached after 75 days without the system, which corresponds to a 20 per improvement over the period. (Dark blue line: Fish weight without Razone. Light blue line: Fish weight with Razone. Dotted line: Expected fish weight with Razone) This could also partly reflect temperature differences in the batches and a change in feed during the project.

Calculating the growth factor (VF3) takes account of the fact that temperature differences occurred in the batches and shows that the group with Razone had better real growth. Average water temperature was 10.2°C in the batch without Razone, and 12°C in the one with the system.

Improved water quality

Tests with Razone have shown promising results. “Our main goal has been to investigate whether water quality improves,” says Stiller. Accumulations have been avoided, and the particle count in the water is reduced.

Samples show a lower content of natural organic material (colour), reduced particle concentration in the water (turbidity) and fewer solid particles – such as mud, fish sludge, feed residues and faeces (suspended solids).

See the figures below.

Reduced content of natural organic material (colour).

Reduced particle concentration in the water (turbidity).

Reduced quantity of solid particles in the water, such as mud, fish sludge, feed residues and faeces (suspended solids).

Areas of application

Razone can be used in hatcheries and land-based fish farms.