Tubkeeper: Hot Tub Water Log

A pool app scales a 20,000 gallon rule down to your 400 gallon tub and gets it wrong. A bottle label assumes some other tub. Tubkeeper works it out for yours. Dip a strip, tap in the colours, and Tubkeeper checks each reading against its target, tells you what is off, in the order to fix it, and how much of which product to add for your tub's volume. Then it tells you when the water is due to change. BUILT FOR A TUB, NOT A POOL • Chlorine or bromine, each judged against its own range • Doses scaled to your gallons and to the percentage on your own product's label • Alkalinity first, then pH, then hardness, then sanitiser, because that is the order that works • No dose moves pH more than 0.4 or alkalinity more than 40 ppm in one go; bigger fixes come in rounds, with a test between • pH worked out with carbonate chemistry at your water's temperature, corrected for cyanuric acid EVERY NUMBER SHOWS WHERE IT CAME FROM Targets are copied from a hot tub maker's published water-care pages, and the limits for getting in from the CDC, with the page one tap away. Every dose comes with its working: litres, grams of active chemical, divided by your label's strength. If the app and a bottle disagree, you can see exactly why. KNOW WHEN TO DRAIN Tubkeeper dates your next drain and refill from people in the water, not the calendar: gallons divided by three, divided by soakers per day. Tap how many soaked each day and the date follows your real use, never later than your own maximum. Filter rinses, deep cleans and new cartridges are tracked too. YOUR LOG, ON YOUR PHONE No account, no sign-in, no subscription. Nothing you log leaves the phone; we could not read it if we tried. A full history shows every test, every dose you added and every chore. Export the lot as a spreadsheet, free, for your records or your dealer. PRO, ONE PAYMENT Logging, the checks, the step order, the drain date, history and exports are free for good. A single purchase adds the exact amount of each product for your tub, with the working, and reminders when a test, a filter job or a drain is due. Tubkeeper does arithmetic from the numbers you give it. It does not test water and does not certify it as safe. Follow your products' labels, add one at a time, and stay out until a fresh test reads in range.

First release. Log hot tub water tests, see what is out of range, and get the dose for your tub’s volume, with the working shown. Drain date from people in the water. No account.