Recently our Customer Experience Team has been getting several inquiries regarding pH drift. Of course, our first question is “what is your alkalinity reading”? As we have discussed in previous editions of Rick’s Remedies alkalinity “sooths” pH to keep it from going all over the place! When we ask this question, the answer is typically, “well, it is right in range between 80-120””… perfect right? No, not always! What we measure is Total Alkalinity with our test kits. Total alkalinity is the sum of Cyanurate Alkalinity and Carbonate Alkalinity. High stabilizer levels (The Protector) can affect our Carbonate Alkalinity which we can refer to as “Adjusted Alkalinity”.
Ricks rule of Thumb: for every 100ppm of stabilizer deduct 30ppm of alkalinity from your alkalinity reading on your test strip.
Here’s a quick example:
Measured alkalinity 120 ppm
Measured Stabilizer 200 ppm
Adjusted alkalinity = 120-60
As you can see in this example Adjusted Alkalinity is 60 ppm, this puts us out of the recommended alkalinity range of 80 ppm-120 ppm, which can make our pH difficult to control.
Here are a few other things to consider:
- High stabilizer levels are caused by stabilized sanitizers such as Trichlor (3 inch tabs) or Dichlor (granular shock from big box stores) to reduce the amounts of stabilizer introduced to your pool consider liquid shock or calhypo shock.
- Read your test strip instructions to make sure you are letting them process the correct amount of time before doing your visual reading.
- Make sure your test strips are stored in a cool place
- Check the expiration date on your strips to make sure they are fresh
Enjoy your pool!