Fine deep-bed filtration, ~10–20 µm
Polishes the water after drum or screen filtration, protecting downstream UV, biofilter and pumps.
A commercial sand filter for aquaculture traps fine suspended solids down to ~10–20 µm in a graded sand bed, polishing water after drum or screen filtration before it reaches UV and the biofilter. FRP or stainless housing, multiport backwash, vertical or horizontal layout. It is a proven sand filter aquaculture solution across RAS and pond operations.
15+ years in aquaculture engineering · Trusted by Japfa Group, Japan Nissui & Tropo Farms · Shipped worldwide in one container
Product Description
Fiberglass Sand Filters are designed to be installed on large commercial installations such as Olympic size pools, diving pools, and water parks. The standard production incorporates a large access manhole in the top for ease of access to the interior. Inside the filter all internal parts and pipework are upgraded to the highest commercial standard, ensuring long life and minimal servicing. As with all other DAVEY filters, the D series is manufactured from totally noncorrosive materials making it an excellent choice for various long-term applications and installations.
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Specifications
Model series integrated from industry practice — final specifications are confirmed by SIGMA's production line per project.
| Model | Capacity | Typical use | Core configuration |
|---|---|---|---|
| SIGMA-CSF-500 | 5–8 m³/h | Small RAS / holding | Φ500 mm · FRP, vertical |
| SIGMA-CSF-700 | 10–15 m³/h | Small–mid systems | Φ700 mm · FRP / SS304, vertical |
| SIGMA-CSF-900 | 18–25 m³/h | Mid-size systems | Φ900 mm · FRP / SS304, vertical |
| SIGMA-CSF-1200 | 30–45 m³/h | Mid–large systems | Φ1200 mm · FRP / SS316, vertical or horizontal |
| SIGMA-CSF-1600 | 50–80 m³/h | Large farms | Φ1600 mm · SS316, horizontal |
| SIGMA-CSF-2000+ | 100 m³/h and up | Industrial-scale culture | Φ2000 mm and up · SS316, horizontal / parallel tanks |
| Filter bed | Graded quartz sand; optional glass media / anthracite / multi-media beds |
|---|---|
| Filtration precision | Approx. 10–20 µm deep-bed filtration — far finer than a screen or drum filter |
| Cleaning | Multiport / backwash valve, pressure-differential triggered — no media replacement |
| Tank material | FRP (fiberglass) / SS304 / SS316 (316L for saltwater) |
| Water feed | Pressurized pump feed |
| Water type | Freshwater / saltwater (also used in pools and public aquaria) |
| Options | Multi-media grading, automatic backwash valve, pressure gauge / sight glass, enlarged capacity |
System composition
Polishes the water after drum or screen filtration, protecting downstream UV, biofilter and pumps.
A simple multiport valve reverses the flow to flush trapped dirt to drain — low running cost.
FRP or 316L stainless construction suits both fresh and salt water.
Configured to the site and the required flow.
Quartz sand graded with glass media or anthracite improves dirt-holding and throughput.
The same high-rate sand filter design serves aquaculture, public aquaria and commercial pools — a mature supply chain.
Application
Video
FAQ
It is a deep-bed polishing stage that captures fine suspended solids (typically down to ~10–20 µm) after coarse solids are removed by a drum or screen filter, keeping the water clear and protecting downstream UV, biofilter and pumps.
When the bed loads up and pressure rises, a simple multiport / backwash valve reverses the flow to flush trapped dirt to drain — no media replacement, just periodic backwash.
The tank is corrosion-resistant FRP (fiberglass) or stainless steel for fresh- and sea-water duty, in horizontal or vertical layouts to suit the site.
Yes — it runs on graded quartz sand and can take optional glass or anthracite for multi-media grading to improve solids capture and flow.
Pentair Triton, Hayward and similar commercial sand filters use the same graded-sand, multiport-valve technology that SIGMA builds — sized instead for pond and RAS flow rates rather than pool duty. SIGMA doesn't resell those brands; our FRP and stainless tanks come off our own production line for fish and shrimp farm use. If you're upgrading from a Triton-style unit to an aquaculture-rated tank, send us your current flow rate and we'll match a model.
Tell us your species, target density and site — our engineers size the system and reply within one business day.