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pHin Smart Water Monitor review: Takes the guesswork out of swimming pool maintenance

Written by Jason Cipriani, Contributor on

pHin Smart Water Monitor

8.0 / 5

pros and cons

  • Takes the guesswork out of water quality
  • Thorough chemical database
  • Expensive for someone with a basic pool
  • Yearly subscription adds to the overall cost

This spring, after canceling a family vacation, my kids' school going remote, my daughter's dance studio closing, and little league baseball being put on hold due to the pandemic, my wife and I finally decided to do something we swore we'd never do: Get an above-ground swimming pool. 

Our three kids asked many, many times, but we always cited the amount of work and maintenance of a pool as a reason not to get one. But, with the kids (and us) stuck at home for an unknown amount of time, we knew we had to do something to give them an outlet, and a swimming pool seemed like the best way to make that happen. 

That was until we started shopping for one. I'll spare you the details, but let's just say, over a course of two months, we camped out in Walmart parking lots, drove a 200-mile circle to check multiple locations, and had two orders canceled on delivery day. 

Everyone had the same idea we did, it seemed, and if it wasn't for a family member who had an old pool they no longer used, we would probably still be shopping for a pool; or would have paid way too much. 

Jason Cipriani/ZDNet

While we were searching for a pool, I was offered a review unit of the pHin Smart Water Monitor. It's a $350 device that floats in your pool or hot tub, routinely takes water readings, and provides guidance in a mobile app. That price includes the first year of service, with each additional year of service currently priced at $99. 

I used pHin, which is admittedly overkill for a $400 above-ground pool but I have to say, it took away all the intimidation and confusion about taking care of a swimming pool that had often been the excuse my wife and I used. 

I set up pHin as the swimming pool as filling from our garden hose, and it immediately started telling me what I needed to do. 

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It's designed to look like, well, a fin, and has a sensor at the bottom of the enclosure that takes over 1,000 readings each week, according to the company. Included in the box is the monitor itself, a wireless bridge to keep it connected to the internet, along with test strips and a card you use to take monthly readings. 

Inside the mobile app, you can view a chart that shows the trend of the water's pH, sanitizer level, and temperate. Whenever the pH or sanitizer is out of the ideal range, you'll receive an alert from the app letting you know what corrective action you need to take. 

The app has a database of common chemicals and brands you can pick from, depending on what's available at your local pool store or big-box retailer. 

Screenshots by Jason Cipriani/ZDNet

Whenever I received an alert that my pool's sanitizer level was low, I could pick the brand of shock or chlorine tablets I had on hand, and pHin would tell me the amount to add to the water to bring it back to an acceptable range. The same goes for making any pH adjustments. 

Then, once a week, you're reminded to do routine chemical maintenance, like replacing the chlorine tablet in the floating dispenser or adding shock to keep the pools clean and clear. 

The only issue I really experienced with pHin was, when the pool was covered, it would lose connection to the wireless bridge, plugged in about 20 feet away from the pool. I eventually tethered the pHin to the side of the pool instead of letting it freely move around, keeping it closer to the bridge, and it took care of any connectivity problem. 

As we took down our pool for the winter a couple of weeks ago, I followed the steps in the app to get the pHin ready for winter. Placing the protective cap that goes over the sensor that's used to take readings, full of pool water, and storing it inside to keep the sensor from freezing during the winter. 

At $350 to get started and then $99 a year after the first year, pHin is clearly something that's meant for someone who has a more sophisticated setup than an above-ground pool from Walmart. That's not to say it didn't help, because it did, tremendously, but it's total overkill for my setup. 

That said, if you have a pool or hot tub you take care of year-round and are tired of constantly using test strips, pHin takes the guesswork out of water maintenance. Heck, you can even have the company send you water chemicals on a subscription basis, so you don't even have to go to the store.