LocalSend vs PoolLevels

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Type in your pool test readings and PoolLevels tells you what the water is doing and the one thing to add. Most pool apps hand you a wall of numbers and a red or green face. PoolLevels computes the saturation index the way a water chemist would, says whether the water is corrosive, balanced or scaling, and gives you a single dose sized for your pool, with the arithmetic printed underneath so you can check it yourself. WHAT IT DOES Real carbonate chemistry. The saturation index from pH, total alkalinity, calcium hardness, cyanuric acid and water temperature, using the Plummer and Busenberg equilibria and Davies activity coefficients, with the cyanurate correction most calculators leave out. One thing at a time. Not a list of six chemicals. One dose, sized for your pool's actual gallons, rounded to a precision you can measure with a jug. The working shown. Every recommendation prints the arithmetic that produced it, so you can see where the number came from instead of trusting it. Safe handling on every dose. Half first with the pump running, circulate, retest, then the rest. Never mix chemicals. Always acid into water. These are on the recommendation, not buried in a help page. Your history. Every reading you save, with the date you tested, so you can see whether last month's dose actually did anything. Strip capture and reading. Photograph a test strip and the app finds it in the photo, records each pad's colour, and can turn those colours into readings by matching them against the bottle's printed chart, corrected where we have paired that strip with a store test. Every reading taken from a photo is labelled as such, any pad whose colour sits far from every chart swatch is marked uncertain, and typing the numbers from a store test is always one tap away. WHAT IT WILL NOT DO It will not guess. Leave out calcium hardness or cyanuric acid and it says so rather than assuming a number. That is not fussiness: omitting cyanuric acid moved a real sample by 0.18 and flipped its verdict from corrosive to balanced. A wrong answer delivered confidently is worse than no answer. It will not track you. No account, no sign in, no advertising. Your readings, your pool and your photos are stored on your phone and nowhere else. The app sends anonymous usage events, such as that a strip was read or the upgrade screen was opened, with no readings, no photos and no location. Purchases go through Apple. Delete it and the data goes with it. It is not a substitute for a test kit, a product label, or a professional. It calculates from the numbers you give it, or reads them from a strip. A strip reading is a first look, not a test kit result. Read the label on the chemical you are actually using, because concentrations differ between brands. Terms: https://poollevels.com/terms Privacy: https://poollevels.com/privacy