If you own a pool, you know the paper test strips. They're slow, not very accurate, and they go bad once the pack is open. In June 2026 I tested the Kactoily 7-in-1 Wi-Fi pool monitor, which measures the water around the clock and sends everything to my phone.
Goodbye test strips
When you want a clean pool for your kids, you need to test the water regularly. Not every strip even measures seven values, and I used to open a pack, use one, and find the rest ruined ten days later. The Kactoily probe floats in the pool and tracks pH, free chlorine, temperature, ORP, EC, salinity and TDS in real time. It also works with salt systems. Our pool uses fresh water with a sand filter, but since we live near the beach, strong winds sometimes blow salt in, and now I can see it.
Calibration and the app
Setup started with a simple pH calibration: three cups of demineralised water, three small powders at different pH levels, and the probe dipped in each in turn to register the values. The app is Kactoily's own and it's great. You set your ideal ranges and get alerts when a value goes off, and you can save a snapshot of the readings on a given date. There's also a small display that I mounted near the pool, so the rest of the family can check too.
It caught a problem straight away
Within an hour it showed my chlorine was very low. I'd recently replaced the skimmer and forgot to put the tablets back. I added three 200 g tablets, and about 20 minutes later the level had gone from 0.3 to 0.9. The ideal range is 1 to 3, so now I know exactly when to add or remove a tablet to stay around 1.5. That's the point: you don't have to be an expert. When friends call me saying their pool is green or grey, I tell them to test the water. This device tells you what's wrong right away.
Extras, one flaw and verdict
The box includes an app guide, a calibration guide and a 22-page water quality guidebook that explains pH, hardness and the rest for complete beginners. I really appreciated that. The one flaw: the display has no battery, so it switches off when unplugged. I'm going to try running it from a small power bank.
If you're buying an above-ground pool and you have kids, I suggest spending the extra couple of hundred to get one. I'm probably buying one for my parents, who just add chlorine without testing, and my kids swim in their pool too. That peace of mind doesn't have a price.