Smart water analysis for whirlpool, spa or bath tub. ICO was also developed for hot water pools and measures and monitors the water temperature, the pH value, ORP / redox (chlorine), the conductivity / TDS (salt content / water hardness).
In our shop you will find different models of the Ondilo ICO. All variants are also suitable for warm water pools (whirlpools, hot tubs, etc.).
The free app informs about the current water status, the weather and warns when the water quality decreases and gives targeted recommendations for optimal and healthy water quality.
ICO, the smart whirlpool analysis system can connect to your network via Wi-Fi or Bluetooth, and thus also to your smartphone or tablet.
The compact water tester protrudes only about 18 mm from the water and thus fits under the usual whirlpool covers. Due to the small design (150 mm height), ICO can also be operated in a skimmer.
The smart device is also equipped with a battery, the charge of which is designed for about 8 months. ICO Spa is conveniently charged via USB cable.
Equipped with an innovative all-in-one sensor, ICO measures the main parameters of your hot tub:
- the water temperature;
- the pH value;
- ORP / Redox (chlorine);
- conductivity / TDS (salt content / water hardness)
ICO Spa can, depending on the variant selected, be used in chlorinated water, bromine water or salt water. Depending on the parameters of your spa and the condition of the water, the app will give you recommendations for action (e.g. adding chlorine) for healthy bathing pleasure.
The free app is available in 10 languages for Android and IOS:
Your pool water quality is in your hands
Compact design & great design
- ICO protrudes only about 18 mm from the water and thus fits under the usual whirlpool covers. Due to the small design (150 mm height and 116 mm diameter), ICO can also be operated in a skimmer.
- The housing is UV and chlorine resistant
- Waterproof to IP68
Durable & Rechargeable Battery
- A battery charge of the water tester, for whirlpool, spa or bath tub, is designed for about 8 months.
- With the included USB cable, ICO can be recharged.

Exact readings & long-lasting sensors
- Precise measurement of water temperature
- Measurement of pH value
- ORP (disinfection rate, determination of chlorine content)
- Conductivity (salt content)
- Durable sensors
- Easy replacement of the sensors thanks to Twistlock system (spare parts are also available here in the shop)
All features of ICO Spa
- Wi-Fi and Bluetooth support
- All-in-One Sensor (water temperature, pH, ORP / redox (chlorine), conductivity / TDS (salt content / water hardness)
- Water analysis specially designed for hot water pools such as whirlpool, spa or bath tub.
- Suitable, depending on the selected version, for water treatment with chlorine, bromine or salt water (salt electrolysis).
- Small design (150mm x 116mm)
- Floats only 18 mm and therefore fits under the usual spa covers
- Due to the small design ICO Spa can also be used in a skimmer
- Long-lasting battery
- Rechargeable battery via USB
- Waterproof housing according to IP68
- UV and chlorine resistant housing
- Free app for Android and IOS available in 10 languages
- Clear presentation of the measured parameters
- Analysis of water parameters
- App gives recommendations for action (e.g. admit cleaning agents)
- Automatic notifications and warnings when parameters deviate
- Integration of current and future weather data
- Storage and processing of the measured data (curves, trends,…).
- Durable sensors
- Easily replaceable sensors thanks to Twistlock system (spare parts are available in our shop)

Specifications of the Spa Thermometer / Water Analyzer ICO Spa
- Sensors: Measurements: pH values, disinfectant (redox), conductivity Estimates: salinity, water hardness
- Power source: 5V battery incl. USB charging cable
- Protection class: IP68
- Dimensions: 150 mm x 116 mm
- Weight: 700g
- Operating temperature: 0 – 40°C
- Color: depending on the selected version: white & bordeaux or white & turquoise
Impact cost estimation
As with all pool testers of this type, the ondilo ICO’s sensors have a limited lifespan. The patented sensors of the Ondilo ICO have an expected service life of 3 to 5 years . Ondilo guarantees at least one year ( 2 years manufacturer’s guarantee on the swimming island and one year on the sensors ). If the sensors need to be replaced, this is very easy thanks to the Twistlock system. It is also not the need to change all three sensors at once. If required, the replacement probes can be reordered individually in our shop and then have a manufacturer’s guarantee of one year.
Currently, prices per replacement probe range from EUR 79 to EUR 89. The free app should remain free in the future.
Your ICO should also be calibrated at least once per season. The ICO is already calibrated at the factory. You therefore do not have to calibrate the ICO during initial commissioning. A calibration set that is sufficient for two calibrations can be found in our shop for around 20 EUR.
Delivery
- Depending on the option selected, you will receive either the ICO Spa, ICO Pool or ICO Salt. All three variants are also suitable for whirlpools, hot tubs or other warm water pools.
- USB charging cable
Downloads
Differences between the various ICO models
ICO Spa
- suitable for water maintenance with chlorine or bromine
- suitable for hot water pools (e.g. whirlpool, spa, bath tub)
- suitable for swimming pools
ICO pool
- suitable for water maintenance with chlorine or bromine
- suitable for swimming pools
- suitable for hot water pools (e.g. whirlpool, spa, bath tub)
ICO SALT
- suitable for water maintenance with a salt electrolysis system
- suitable for swimming pools
- suitable for hot water pools (e.g. whirlpool, spa, bath tub)
- yellow ORP sensor (with gold contacts / optimized gold measuring cell for salt water) instead of orange (standard platinum measuring cell)