Fine Solids Removal for Aquaculture & RAS
In recirculating systems the same water meets the fish again and again. Pile cloth filtration keeps it reliably clear — gently, in continuous operation and without interrupting the loop.
Why Fine Solids Are So Critical in the Loop
In a recirculating aquaculture system (RAS) the same water is treated and returned to the fish over and over. Anything not removed accumulates: uneaten feed, faeces and fine suspended solids cloud the water, stress the fish and feed unwanted bacterial growth. Reliable fine-solids removal is therefore the foundation of fish health and stable water quality.
Just as important: the fine-solids load would otherwise overload the sensitive downstream stages. A cloudy inflow reduces the effectiveness of UV disinfection and adds to the biofilter’s burden. Removing the solids early and gently protects the entire downstream treatment train.
How Pile Cloth Filtration Fits In
Pile cloth filtration works as a mechanical fine-solids stage in the loop — typically after coarse solids removal and before the biofilter. The dense, three-dimensional pile forms a depth-filtration bed: during filtration the flexible fibres lie flat and retain even fine particles throughout the fibre volume. For cleaning, the fibres stand up during suction and release the solids in concentrated form.
Because filtration and cleaning run at the same time, the loop keeps flowing without interruption — decisive where a steady, oxygen-rich flow to the fish must never stop. The filtration grade is matched to the particle load and the required water clarity.
Operational Advantages at a Glance
Uninterrupted loop
Filtration and suction cleaning run at the same time — the oxygen-rich flow to the fish never stops for a backwash.
Protects biofilter & UV
Clear water eases the load on the downstream biofilter and lets UV disinfection work at full transmission.
Fine depth filtration
The three-dimensional pile retains fine particles throughout the fibre volume — not just on a surface.
Gentle & water-saving
Suction cleaning removes the solids in concentrated form and uses only a fraction of throughput as rinse water.
Keeping Biofilm in Check: the Bioactive Pile Cloth
Warm, nutrient-rich aquaculture water encourages biofilm on every wetted surface — including the filter media itself. Our Bioactive pile cloth carries innovative silver particles (patent pending) that help limit biofilm formation on the cloth, which can support more stable filtration between cleaning cycles.
It is a media-side measure to keep the filter itself cleaner — not a substitute for the system’s disinfection stage.
Already running a disc or drum filter in your aquaculture system? We supply matching replacement pile cloth media. Our cross-reference tool helps identify the right R+F equivalent for your current cloth.
Frequently Asked Questions
Design Filtration for Your Recirculating System
Whether new build or retrofit — we support media and grade selection for your water and supply replacement cloth for existing filters.