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

Sutro vs. Keto Review - Which is the better one?

There are many pool/spa/hot tub water monitors available, and it can be hard 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 re-balance 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 re-balance your water and how many 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 replacement once per month 
  • Needs subscription

Get the Sutro pool monitoring system here.



The Keto A.I. Smart Skimmer is an automated pool water monitoring device that checks the sanitizer (chlorine), pH, water level, and temperature. 

Unlike most other pool monitors, it does not float in the water and is installed directly into the skimmer basket. Its positioning allows it to measure the pool water level, detect if the pump is running, and if your skimmer basket needs cleaning. 

Keto A.I. Smart Skimmer works with saltwater pools and chlorine-based swimming pools. It can directly connect with a wi-fi network to track the pool chemistry from anywhere. It also connects to your smartphone via Bluetooth if you are nearby your pool. 

This monitor works on solar power and has an LED light fitted on top, indicating your pool water's health.  


Works well with 

The Keto A.I. Smart Skimmer works with:

  • Chlorine Based Pools 
  • Saltwater Pools


The Keto A.I. Smart Skimmer costs $395 and does not offer any subscription. You do not have to buy any extra cartridges or pool chemicals along with the device. Here’s a list of items included in the box:

  • Keto A.I. Smart Skimmer Unit
  • Three Round Adapter Rings
  • Charging Cable
  • User Manual


  • It runs on solar power. No need to change batteries.
  • Connects via wi-fi and Bluetooth.
  • It fits the skimmer basket directly. Doesn’t float and stays concealed.
  • No need for cartridge replacements
  • LED indicator for quickly assessing the quality of pool water


  • Limited to saltwater and chlorine pools
  • Not very accurate after a couple of months
  • It needs to be placed into the skimmer basket. 




The Sutro Pool Monitor is a more accurate and technically advanced option when compared to the Keto Smart Skimmer.

While Sutro gives values of different parameters, Keto delivers the ORP value for an overall analysis of the pool water chemistry. 

Sutro has a long battery life, and the Keto runs on solar power and rarely needs charging through the USB port. Additionally, Keto installs directly inside the skimmer basket and has an LED light to signal if the pool water is appropriate.

This means you only sometimes need the app for a quick check. 

Since Keto does not need cartridge replacements, its accuracy suffers in the long run. Sutro uses the gold standard for water testing, and its results are incredibly accurate.

Sutro costs $100 more than the Keto, but their quality, accuracy, and customer support are far better than that of the Keto A.I. Smart Skimmer.

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