Dip a test strip, enter your readings, and SpaCheckup tells you exactly how much of each chemical to add — measured for your spa’s size and sanitizer. No math, no guesswork, no subscription.
No chemistry degree needed. If you can dip a strip, you can keep your water perfect.
Use any standard test strip — AquaChek, Taylor, or the ones that came with your spa. Match the pad colors to the bottle like you always do.
Tap the readings into SpaCheckup: pH, sanitizer, alkalinity, and hardness. Clear steppers and target ranges show you where each number stands.
Get precise doses in ounces, teaspoons, or grams — calculated for your spa’s exact volume, sanitizer type, and product strength. Log it and you’re done.
SpaCheckup does one job exceptionally well: keeping your water safe, clear, and comfortable.
Not “add some pH down” — the precise amount for your spa’s volume, down to the fraction of an ounce, with the reason why.
Full support for both sanitizer systems — including bromine bank establishment after a refill and MPS shock guidance.
Local notifications for water testing, shock treatments, filter rinses, and drain & refill — on the schedule you choose. Part of the one-time unlock.
Every test and treatment is logged automatically. Unlock your complete history and trends to see exactly how the water tracks across the whole season.
A calm, glassy dark theme for late-night soaks. Follows your system setting or set it manually.
No account, no cloud, no tracking. Every reading stays on your device — SpaCheckup never collects or transmits your data.
Whether you just filled your first spa or you’ve been chasing cloudy water for years.
The wizard sets you up in under a minute — spa size, sanitizer, units. From your very first test strip, you’ll know exactly what to add and why.
Cloudy water is almost always a chemistry problem. SpaCheckup pinpoints which reading is off and fixes causes, not symptoms — in the right order.
Skip the dosing charts and mental math. Enter readings in seconds, get doses tuned to your exact product strengths, and keep a clean treatment log.
Clear readings, honest recommendations, and a home screen that tells you at a glance whether the water is ready.
Know at a glance if the water’s ready
Exact doses with the reason for each
Reminders that keep you on schedule — part of the unlock
Free guides that teach the chemistry — no app required. Though it does make things easier.
The whole picture in one place — the five numbers that matter, their target ranges, how to test, and how to fix each one. The best place to begin, with links to every deep-dive guide below.
Read the complete guide →What each pad measures, how to get an accurate reading, and what the numbers should be for a spa.
Read the guide → Fix itWhy spa pH drifts up, what pH decreaser actually is, and how to dose it without overshooting.
Read the guide → TroubleshootingA step-by-step troubleshooting guide, from sanitizer levels to filters — in the order that actually works.
Read the guide → DecisionsAn honest comparison of cost, maintenance effort, and feel, and how to switch if you change your mind.
Read the guide → RoutineA realistic testing schedule based on how often you soak — plus the moments you should always test.
Read the guide → Inflatable tubsIntex, Coleman SaluSpa, Lay‑Z‑Spa — the full routine, and the few things that are genuinely different on a small tub.
Read the guide → BuyingShopping for one? Our current top picks by category — best overall, best budget, best for cold climates, and more.
Read the guide → BuyingThe short list we’d actually buy — test strips, sanitizer, pH control, and more — plus how often you really need to restock each one.
Read the guide →
Get exact chemical doses for your hot tub in seconds — free to download, no subscription, no guesswork.
Free to download · no subscription · no ads