Editorial policy

How rules are sourced. Every rule behind a calculator is traced to a community source — subreddit wikis, long-running forum threads, manufacturer labels or dated community threads — and carries a confidence grade: A for measured or official facts, B for consistent community consensus, C for contested rules of thumb shown as an order of magnitude.

Disagreements are shown. When the community holds two or more positions (for example filter turnover at x4 versus x10), the page shows both with their sources and conditions. We do not silently pick a winner.

Estimates are labelled. Numbers that depend on the individual fish, feeding or setup are marked as estimates, and pages state what changes them.

Corrections. A correction request is checked against the original source. If the source changed, the rule, the page and the confidence grade are updated; if the disagreement is real, it is added to the page instead of being hidden. Corrections are logged with the date.

Independence. gillcalc takes no payment for a calculator result, ranking or recommendation. Ads, if present, do not influence the rules. Manufacturer data is used only as a label fact and is dated.

Data and privacy. Calculators run in your browser. See the privacy page.