The COLDEP process resolves the main technical limitations encountered by water recirculation systems in fish farms:

  • Decrease in the oxygenation level of the water.
  • Acidification of water, due to too much CO2 dissolved.
  • Abundance of small particles <30µm which are not captured by conventional filters, which clog drum filters and reduce the effectiveness of UV treatments.
  • Energy cost of the solutions implemented to solve these problems.
particulate extraction - water clarification - biosecurity

Treatment of fish water in SAR

Microbubbles created in the system trap impurities as they rise and create a froth at the top of the column. This foam which is sucked up by the vacuum carries with it the particles, then trapped inside. These extracted particles are between 0.3 and 30 µm and are not trapped in conventional systems.

Minimum size of the particles extracted

Energy consumption per m³ of & #039; treated water


Reduction of bacterial load

less viral load

Particulate extraction by the COLDEP system also allows bacteria and viruses to be trapped, thus ensuring the biosecurity of the installation. Clarification of the water also makes it possible to guarantee a optimum UV efficiency.

In addition to particles, a large part of dissolved organic matter is extracted: lhe COLDEP process makes it possible to extract geosmin from water and therefore reduce the presence of off-flavors.

There is the possibility of extracting continuously or only a few hours a day.

Dissolved gas management

Regulation of O concentration2, CO2 and N2

The bubbles associated with the vacuum created at the top of the column make it possible to achieve unmatched aeration and degassing efficiency. In addition, the COLDEP process makes it possible to prevent any risk of nitrogen supersaturation.


Minimum oxygen saturation level


Reduction of the quantity of CO₂ in a single pass

The opinion of professionals


At ACIPENSER we have 200 m3 holding tanks for female sturgeons to optimize the taste of their caviar. Before the installation of the COLDEP column, we occasionally encountered off-flavor problems on our caviar. Thanks to the combination of airlift filtration and ozone treatment we were able to remove these unwanted tastes and obtain a constant quality of caviar.

Alexander Warrior

General manager, ACIPENSATE