👨🔬8. Understanding pool chemistry - pH, ORP, and Chlorine
Last updated
Last updated
If you have a Clyr sensor installed on your system you will be able to monitor your chemistry in real time. They will show up on your home screen and in the water quality page. Let's dive in to see what these items are and how to use them.
The Clyr chemistry sensor reads pH every 5 minutes (or we can show you how to request the latest values as well). pH in pool water is a measure of how acidic or basic the water is, and keeping it in the right range (usually 7.2–7.8) ensures swimmers’ comfort and helps sanitizers (like chlorine) work effectively. If the pH is too low (acidic), it can irritate eyes and corrode pool equipment; if it’s too high (basic), the water may become cloudy and reduce chlorine’s effectiveness. To balance pH, use pH increaser (often soda ash) if it’s too low or pH reducer (such as muriatic acid) if it’s too high, always following the directions on the product label.
As an example, if your pH drops below 6.8 it can damage the heater if the heater is turned on. This is a common problem and can lead to costly repairs!
Let's say you have high pH like the picture below. How do you fix it? In the Clyr App, just click on the pH card and it will take you to a screen that says "Pool Care" with exact instructions on what you should do.
Please make sure that the gallons of your pool are correct as this can possibly lead to overdosing if you're not careful.
ORP might be something you've never heard of but it's been in the pool industry for over 40 years! ORP (Oxidation-Reduction Potential) measures how effectively your pool’s sanitizer—like chlorine—can kill germs and keep the water clean. Think of it as the “strength” of your pool’s sanitizing power. Free chlorine, on the other hand, is the actual amount of chlorine available in the water. When free chlorine is balanced (not too low or too high), ORP readings tend to be higher, which means your pool is doing a better job at zapping unwanted bacteria. By keeping both ORP and free chlorine in recommended ranges, you’ll ensure your pool remains safe, clear, and inviting. A good ORP level is 550-800 mV.
In order to raise your ORP level, you can click on the card in the home page and go to pool care steps, the same as pH!
Unless you have a sensor from Clyr which explicitly measures free chlorine, you can still get an estimated free chlorine reading in the app! We have a pretty smart algorithm that can take your pH, ORP, water temperature, and CYA to calculate free chlorine.
All you need to do is go to the free chlorine card, hit the small "pencil" and enter in your Cyanuric Acid Content in ppm (CYA). If you don't have your CYA reading, you can go to a local pool store to get this measured or order test strips online. Good CYA is usually in between 10-50 ppm.
What to do if the Clyr app says your Free Chlorine is X but the pool store says it's different? There's a couple of things you can do:
Check your CYA content - CYA above 50ppm can really reduce how effective your chlorine is and will lower ORP overall
Salt content - if you have high salt in your pool, this can also lower ORP and free chlorine estimation
ORP Sensor Powered for 24 hours - if you just finished installing your sensor, please wait 24 hours with the sensor powered on in order for the readings to become more accurate.
If you have a variable speed pump hooked up to your pool and it is configured as a main filter pump, filtration will be calculated.
The rule of thumb in the pool industry is that the total gallons of your pool water should be filtered through 2x in a 24 hour period
Based on the rule of thumb above, Clyr actually keeps track of how much pool water you've filtered to this standard and shows you this as a daily percentage!
