Frequently Asked Questions

Q: What is the difference between AquaChek and the other pool and spa test strips available on the market?
A: AquaChek is the top-selling brand of pool and spa test strips in the world. AquaChek test strips undergo stringent release qualification. Constant monitoring of the manufacturing process ensures that the finest test strips are available for your use. In fact, our company has earned the internationally recognized ISO 9001 certification by following strict quality standards.
   
Q: What information supports the accuracy of test strips?
A: AquaChek test strips are manufactured and released against standard reference procedures from the 17th Edition of Standard Methods For the Examination of Water and Waste Water.
   
Q: Is DPD more accurate?
A: The DPD test for chlorine can be affected by interferences, such as an over-abundance of monochloramines or potassium monopersulfate (used for shock-treating pools). These can give a false positive reading for free chlorine with the DPD chemistry. Recognized technical studies are available to support these claims. In addition, the DPD test requires careful technique and several steps to get the best test.
   
Q: My DPD test kit shows I have 3 ppm Free Chlorine while my AquaChek test strips say I have 0 ppm Free Chlorine. Which test is correct?
A: If there is a high level of combined chlorine in your pool or spa, it is likely the DPD test is showing a false positive for free chlorine and your AquaChek Pool & Spa Test Strips are giving an accurate reading. For more detailed information, please visit the following link to the technical bulletin about test kit differences.
   
Q: I have added a significant amount of Chlorine and the AquaChek test strips still read 0 ppm for Free Chlorine-why?
A: If testing for Free Chlorine using a DPD test kit, be aware that high levels of combined Chlorine, or Chloramines can cause false positives when using DPD #1 test for Free Chlorine. In order to confirm this is taking place, take a small sample (3-4 cups of water) out of the pool. Add a small amount of Chlorine (e.g. a teaspoon of bleach or several dichlor granules) directly to the sample to be sure that a Chlorine residual can be established. You should be able to measure the Free Chlorine right in the sample almost immediately after the Chlorine has been added. This is representative of the rest of the pool. If a Chlorine residual can be established in a small sample, then you will know that the actual pool can be treated in the same way. Additionally, the DPD or OTO test will measure the same as the strips at this point confirming that the combined Chlorine was causing a false reading for the liquid/tablet test.
   
Q: Why aren’t there more values on the color charts for AquaChek products?
A: AquaChek products are designed to be user-friendly for pool and spa owners. To make them easy to use and understand, we ensure that color values can be clearly differentiated so accurate decisions can be made regarding water treatments.
   
Q: What is test strip shelf life?
A: We ship most of our products with a 24-month shelf life, at a minimum. A few of our speciality products, such as test strips for Iron and Copper have no less than an 18-month shelf life. Each bottle is noted with an expiration date. Even though the effectiveness of all liquid test reagents and test strips degrade over time, some of our competitors do not date their product. Dating the product is just one way AquaChek ensures product performance and quality.
   
Q: How accurate are the test strips?
A: Test strips are at a minimum comparable in accuracy to liquid color comparator tests. AquaChek strips are more convenient and we believe they actually deliver greater accuracy. The strips reduce the chances for human error associated with liquid kits, which require measuring samples and counting drops of reagent.