Sutro vs. WaterGuru Sense Review - Which is the better one? - Sutro, Inc

Sutro vs. WaterGuru Sense Review - Which is the better one?

Many pool/spa/hot tub water monitors are available, and it can take a lot of work to compare them. Don’t worry; we are here to help and help you get the best one for your case.


The Sutro checks water chemistry levels like ph and chlorine (or bromine) three times daily, alkalinity once daily, and temperature every hour.

The Sutro monitor is a floating device that can be placed directly inside your pool, spa, or hot tub. 

When the Sutro detects that your water is not balanced, it will notify you and suggest how much and what types of chemicals you should add to rebalance your water again. 

For this, the Sutro measures:

  • Temperature
  • Free Chlorine
  • Acidity (pH)
  • Alkalinity
  • Bromine

A result from Sutro will tell you exactly what to add to rebalance your water and how much chemicals it needs. 

You could scan the barcode on the chemical brand you have on hand, and Sutro will automatically calculate how much you need to add. 

The Sutro app, which can be paired with the Sutro Monitor, is available in the Apple and Google Play Store.

Works well with

The water monitor works the following types of Pools, Hot Tubs, and Spas: 

  • Chlorine
  • Saltwater
  • Mineral
  • UV
  • Bromine


The price for the Sutro device starts at $499, requiring a monthly subscription of $29 for the primary or $39 for the premium subscription. 

The subscription covers the following:

  • BASIC ($29/Month)
  • On-demand cartridges shipped to your doorstep; Expert recommendations based on the chemicals you own; E-mail and chat support.
  • PREMIUM ($39/Month)
  • Everything in BASIC + Front line VIP Support with a certified CPO, Weekly Water Health report, Monthly Pool Pro Consultation, Detailed Historical Graph


  • Monitors water chemistry 3x times a day 
  • Uses LaMotte and Taylor reagents, the gold standard of the pool industry
  • It tells you which chemicals to add, how much, and when to add them 
  • All chemical brands are compatible
  • It works with hot tubs and spas
  • It can be used outdoors


  • The reagent cartridge needs to be replaced once per month 
  • Needs subscription


Get the Sutro pool monitoring system here.


The Waterguru device can measure your water temperature, free chlorine, and pH levels once per day. 

The device needs to be placed inside your skimmer. 

When Waterguru detects that the water chemistry is not balanced, it will notify you through the app.

The WaterGuru app is available on the Apple and Google Play Store. 

Works well with:

The WaterGuru monitor works with the following types of Pools

  • Chlorine Pools 
  • Saltwater Pools

WaterGuru measures the following data points once per day:

  • Free chlorine (FC)
  • pH 
  • Temperature


The Price of the Waterguru is $325. The test Cartridge or “cassette” needs to be replaced regularly and is said to last eight weeks. The price starts at $19.99 for one cassette and three for $49.95



  • The price for the device is lower than Sutro
  • Also uses colorimetry, which is the best way to measure water chemistry (unlike ORP and pH probes)


  • Measures only once per day
  • It uses “cassettes” that need to be exchanged regularly
  • If your skimmer is squared, you need to buy an extra part that fits 
  • Test Cartridge has to be exchanged regularly 
  • It’s not recommended for hot tubs, spas, or outdoors
  • Only works on inground pools


Despite the Waterguru being slightly cheaper than Sutro, the Sutro seems better in the long run. 

The reasons? Better accuracy due to gold standard water measurement and more data points to keep the water balanced, not to mention the possibility of adding a historical graph option 

If you also have a spa or a hot tub, you’d prefer the Sutro since it is an element’s resistant device and works with all types of pools.



Where can it be placed?

Floats in the pool

In the skimmer 

Measures Temperature 


1x day 

Works on all these types of pools

Chlorine, salt water, mineral, UV, and bromine

Works in hot tubs

Test pH

3 x a day 

1 x day 

Test free chlorine

3 x a day 

1 x day 

Test bromine

3 x a day 

Test total alkalinity 

1 x a day 

Uses reagent chemistry

It tells you how much chemicals you need to add 

Works with over 2,300 chemical brands

Customer Service

E-mail, Chat, Phone

E-mail, Phone

Monthly Subscription 

Basic $29/m 

Premium $39/m

How does the water get measured?

LaMotte and Taylor Reagents

Optical Sensor that reads the test strips 

iOS App

Android App

Historical Graphs of water parameters 

With Premium Subscription 

Manufacturer Warranty 

1 year

1 year


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