Effluent Water

Effluent water treatment is a critical step in land-based fish farming. It involves filtering and cleaning the water being expelled from the fish farm. Water exiting a fish farm, is required to be filtered and cleaned to ensure minimal impact on the natural environment.

Inlet Water Treatment

Effluent Water Treatment
Effluent Water Treatment
Effluent Water Treatment

AL-2 Sludge Treatment

Chemical Treatment of Wastewater

Wastewater often cannot be sufficiently treated through mechanical filtration. Therefore, our solution uses chemical pretreatment to comply with discharge requirements or achieve a quality that allows the water to be recycled.

We recommend treating the wastewater with our separation unit, where we can remove unwanted substances such as organic matter, grease, oil, phosphorus, and heavy metals. Wastewater treatment is carried out by treating a continuous flow, where we start by coagulating and precipitating the unwanted substances, after which they are collected into larger particles in a flocculation process that can be gently separated from the water phase on the belt filter.

The treated water can be discharged to the sewer without any additional charge or used in a recycling process elsewhere in the company.

What is mechanical treatment and its benefits?

AL-2’s separation system operates as a continuous flow system for wastewater. By using our belt filter, your company ensures a mechanical treatment of water after chemical precipitation, where optimal operation of the belt filter ensures good removal of particles through the built-up filter mat.

When wastewater is treated, it also undergoes a chemical process. The wastewater is pumped into the mixing tank of the separation plant, where chemical treatment of the water occurs. Chemicals are added for precipitation of particles and pH regulation. Then polymer is added to form flocks of particles that can be more easily filtered out. The flocks are led out to the belt filter, where they are filtered out on the filter belt to achieve separation of sludge/particles and purified water.

This ensures a gentle and effective removal of particles and impurities. By using mechanical treatment of wastewater with AL-2’s solutions, you always achieve high operational reliability with low noise levels.

When you perform a combined chemical and mechanical treatment of wastewater with AL-2’s separation plant, the process runs completely automatically. Once the plant is installed, it requires minimal labour and is controlled and monitored through our robust PLC control system, which have been developed through many years of experience.


Hard water contains high levels of minerals such as calcium and magnesium, which can negatively impact the health and growth of fish. By utilizing microfiltration systems like drum filters or disc filters, the hard water can be effectively treated and purified. These filters are designed to remove debris, sand, and other imperfections from the water, ensuring a clean and optimal environment for fish to thrive.

NP Innovation

NP Innovation specializes in the development, production, and sale of pressure-less filter systems, specifically drum and disc filters. These filters are known for their exceptional functionality, design, and longevity, making them a top choice in the market. With their reliable performance, low maintenance requirements, and versatility, NP Innovation filters are widely used in industrial facilities for the filtration of inlet water and wastewater.


HydroTech filters have been widely used in aquaculture for over 25 years. They provide durable and user-friendly filtration solutions to fish farms worldwide. With their robust construction and minimal moving parts, HydroTech filters ensure long-term reliability and low maintenance costs. They offer both Drumfilter and Discfilter options, and our team at GroAqua will assist you in selecting the best filter based on your specific needs and flow rates.

Inlet Water Treatment
Inlet Water Treatment

UV Disinfection

With the use of UV systems, the water is subjected to ultraviolet light that effectively disinfects and eliminates harmful microorganisms before it enters the fish farm. The UV light targets bacteria, viruses, and parasites by damaging their DNA, rendering them inactive and unable to cause harm to the fish. By incorporating UV filters into the water treatment process, land-based fish farms can ensure that the water is free from pathogens, providing a healthier and safer environment for the fish. 


Wedeco, a subsidiary of Xylem, is one of the largest manufacturers of ozone and UV systems globally. Their UV disinfection solutions, approved by the Norwegian Veterinary Institute, ensure the health and safety of fish by preventing harmful organisms. With high UV-C output and efficient lamps, Wedeco UV systems offer real-time monitoring and precise control for optimal performance. Trusted worldwide, Wedeco UV systems are installed in various industries, including fish farms and sewage treatment plants.

Ozone Generation

Ozone systems are another important component in inlet water treatment for land-based fish farming. Ozone, a powerful oxidizing agent, is used to remove impurities and disinfect the water, creating a healthier environment for fish. By introducing ozone into the water treatment process, harmful bacteria, viruses, and other microorganisms can be effectively eliminated. Ozone reacts with organic matter and contaminants in the water, breaking them down and rendering them harmless.


Wedeco’s ozone systems provide compact and plug-and-play equipment for aquaculture applications. Along with the ozone generator, their systems come with control cabinets, dosage control based on water flow, a pump-venturi system, and oxygen supply if necessary. We are proud to offer a diverse selection of Wedeco Ozone systems.

Inlet Water Treatment

See More on the Webshop

To explore our full range of products and services, we encourage you to visit our webshop. Our webshop offers a wide range of products and services for aquaculture and fish farming, including aeration systems, fish handling equipment, filtration systems, feeders, and monitoring tools. Browse our selection to find the perfect fit for your operation.

We are here to
guide you

Do you have questions, speculations or want to
chat about possibilities, get in touch.

Mark Farquhar

Sales (UK & Ireland)


Lindsay McCrae

Sales (UK & Ireland)