Guide topic
Cold Plunge Water Care
Plain-English, source-cited guides to keeping plunge water clean and safe.
Guide
Chlorine vs. hydrogen peroxide: the dosing math
How to pick a sanitizer, the per-fill dosing numbers, and the one mix you must never make.
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Guide
How often should you change cold plunge water?
A cadence chart by tub type and sanitizer, plus when to clean the filter.
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Guide
Why is my cold plunge water cloudy?
Five causes, how to tell which one you have, and the fix for each.
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Guide
Cold plunge water testing: strips, targets, and how often
The three readings that matter, the strips that measure them, and a cadence that sticks.
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Guide
What temperature should a cold plunge be?
A starting range by experience level — and why colder isn't automatically better.
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The app for this
Frost — Cold Plunge Care
An iOS app that does the dosing math, sets your maintenance cadence, and diagnoses cloudy water — for chlorine or peroxide, chiller or DIY. No subscription, no ads, works offline.