Water treatment for fish farms and RAS
Fish farms, hatcheries and recirculating aquaculture systems (RAS) depend on clean, stable and pathogen-free water. AFG manufactures the filtration, disinfection, reverse osmosis and wastewater systems that make it, and AFG Dubai supplies them in the UAE and GCC.
Water for aquaculture comes from the sea, from wells or from the municipal network, and each source brings its own problems: sand and silt from intakes, salinity that does not suit the species, chlorine in municipal water, and bacteria and parasites that can spread quickly through a farm.
In a RAS most of the water is cleaned and returned to the tanks, so the make-up water and the loop treatment decide how stable the system runs. What leaves the farm also matters: effluent has to meet discharge rules, and treated water can often be reused. Every system is sized from your water analysis, flow rates and stocking plan.
Problems we solve
Solids in intake water
Sand, silt and particles from sea or well intakes clog pipes, foul equipment and stress fish.
Pathogens and disease risk
Bacteria, viruses and parasites spread fast in tanks and recirculating loops.
Make-up and hatchery water quality
Salinity, chlorine and dissolved contaminants in the source water have to match what the species and life stage need.
Effluent and water cost
Farm effluent must meet discharge limits, and every cubic metre reused lowers intake and treatment demand.
Which systems we use
Further reading
Questions buyers ask
Can UV and ozone be used on recirculating (RAS) water?
Yes. UV-C reactors are widely used on RAS loops and intake lines to reduce bacteria and viruses without adding chemicals. Ozone also oxidises fine organics and improves clarity, but its dose must be controlled so no residual ozone reaches the fish. The right combination is chosen from your flow rates and water quality.
How is seawater intake treated for a marine farm?
A typical train screens the intake with self-cleaning filters, removes finer solids with sand filtration or ultrafiltration, and disinfects the water with UV or ozone before it reaches the tanks. Depth of treatment depends on the intake location, the season and how sensitive the species and life stage are.
Is municipal water safe to use as make-up water?
Not without treatment. Municipal water is disinfected with chlorine or chloramine, which is toxic to fish even at low levels. Activated carbon filtration removes chlorine before the water enters the system, and the rest of the treatment is set from a full water analysis.
When does a fish farm need reverse osmosis?
When the source water is too saline or carries dissolved contaminants that filtration cannot remove, for example for freshwater hatcheries on brackish wells. RO permeate is very low in minerals, so it is usually blended or remineralised to the quality the species need.
What information do you need to design a system?
The water source and a recent analysis, the intake and make-up flow, whether the farm is flow-through or RAS, the species and life stage, and the discharge or reuse target for effluent. Send these through the quote form and we will reply with the next steps.
Ready to talk about your water?
Capacity and source water are enough to start. A full analysis lets our engineers choose the right membranes and pre-treatment.