What is the Best Tester for Pool Chemicals?
The most common pool chemicals to test are: chlorine, pH and total alkalinity. There are basically three methods for testing the common pool chemicals.
1.) Drip Sticks or Test Strips – These are small trips of a cardboard looking material that are dipped in the swimming pool water and then matched to a set of colors on the container they come in. Each spot on the strip tests something else. These are easy to use and give a quick and dirty read on the water. The down side is they are not as accurate as other methods. The test strips also typically test calcium hardness (water hardness) and stabilizer (cyanuric acid). We found when we were measuring with test strips that the tests could be up to 20% off on these two extra chemicals.
2.) Digital Tester – We don’t have extensive experience using these so I’ll have to go off of what I’ve heard by other professionals in the industry. I’ve heard they are convenient and obviously it is nice to have a sophisticated looking digital readout. However I’ve heard several of the leading brands have trouble with accuracy over time. I also know some of them cannot be calibrated. We do use a digital tester for salt, water temperature and TDS that is “calibrate-able”. We calibrate them every 30-60 days to ensure they stay accurate.
3.) Titration (drip) Tester – These use reagents with colored solutions. The solutions are added to the tester as drops and then color matched to determine the readings. Titration refers to the swirling of the water to combine reagents and show the color. It is important to make sure the reagents are not too old. Old reagents lose their accuracy badly. Fortunately our service technicians see enough pools in a week to go through the major reagents every few days.
We use a Taylor commercial titration based test kit. It’s accuracy has been the best we can find thus far. We keep them covered and stored in our trucks in such a way so as to be out of the sun. One of the reagents in particular (r0004) actually gets neutralized within hours of direct sunlight. So we work hard to keep buttoned down in their cases.