Sources and Corrections

Method v1, checked October 14, 2026. This page records the basis for the two pool-flow tools, how product pages are sourced, and how to report a factual problem.

Flow and geometry method

Rectangle volume is length × width × average water depth. Round volume is π × diameter² ÷ 4 × average water depth. Ellipse volume is π × length × width ÷ 4 × average water depth. Measurements are in feet; multiply cubic feet by 7.48051948 for US gallons.

Planning flow in US GPM is gallons ÷ (60 × turnover hours). Longer turnover gives the lower flow. These are entered scenarios, not sanitation rules or a guaranteed daily schedule. An irregular or stadium-shaped pool needs known filled gallons rather than the ellipse formula.

Pump curves and equipment limits

An operating point needs known total dynamic head and the exact US 60 Hz curve at the stated speed. The pump tool interpolates only between two adjacent supplied points. It never extrapolates or converts pool volume to horsepower. A filter pressure reading alone is not total dynamic head.

Filter area is calculated only from known operating flow and a rate supplied by the exact model's source. No generic sand, cartridge or DE rate is assumed. A failed known limit is incompatible; missing data is unknown. A pass against supplied values does not verify the installed system.

Method sources

Product pages

Product reviews and roundups use the maker's own product page, the maker's manual where one exists, and the Amazon US listing for the exact item. Each page names its sources in its body, and many show the date we checked them. Where a listing and a maker page disagree, we keep the figures apart and say which one we used, and the maker's page wins over broader catalog wording. We do not test products, and we do not use prices, ratings or reviews in our picks.

A model we could not match to an exact maker version is marked unconfirmed rather than filled in. Safety and recall statements point to the official notice, such as the US Consumer Product Safety Commission.

Report a correction

Use the contact page. Include the page URL, exact equipment model, disputed field and official source URL or document page. Don't include passwords, medical details or private account information.

Revision record

October 14, 2026: initial method v1 recorded. The worked 10,000-gallon example with 6-to-10-hour scenarios gives 16.7-to-27.8 GPM. No model inventory, generic filter constant or default operating recommendation is part of this method.

See the filter flow tool, pump flow tool and editorial policy.