Interactive Calculator · 2026
Filter Sizing Calculator (PSF/ACF)
Size a pressure sand filter (PSF) or activated carbon filter (ACF) from flow and filtration rate. Enter the daily flow, the filtration (loading) rate and operating hours — get the vessel diameter every filter design starts from.
Flow & filtration rate
Total volume the filter must treat per day.
Hours the filter actually runs — sets hourly flow.
Loading rate across the media bed — typically 8–20 m³/m².hr for a PSF/ACF. Lower = larger, gentler filter.
How filtration rate drives filter area
Required filter area at each filtration rate for 10 m³/hr — a higher rate shrinks the filter but pushes the media harder.
Highlighted bar = your selected rate of 12 m³/m².hr
How this is calculated
- Design flow = flow ÷ operating hours = 200 ÷ 20 = 10 m³/hr.
- Filter area = design flow ÷ filtration rate = 10 ÷ 12 = 0.83 m².
- Vessel diameter = √(4 × area ÷ π) = √(4 × 0.83 ÷ π) = 1.03 m.
Indicative sizing for concept planning. A detailed design must also fix media depth, freeboard, backwash rate and vessel standard — confirm with a qualified consultant before procurement.
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