DoubleCheck Water Hardness Test Kit 200 Strips with Sample Cup - Hard Water Testing Strips (0-25 gpg / 0-425 ppm)

Use to test water for swimming pools....works great!

Worked perfectly!

Very easy to use and fast. We keep them in our water bay on the RV to check water hardness at the places we stop. It's nice to be able to perform a water hardness check in under a minute. My only recommendation would be for them to provide a rigid plastic box to keep everything in when not in use. We use a small Tupperware container to keep everything clean and dry.

used to check whether our water softener was doing its job (was not just like we thought). Needed something to show the repair company how hard the water was

These test strips provide accurate water hardness measurements. My previously purchased test strips were well beyond their expiration date and providing erroneous test results. I would recommend paying close attention to the expiration date of previously purchased test strips.

typical kit - works well - nice to have the strips stored in a sealed container to preserve them better

Very handy!

It’s difficult to distinguish water hardness on the color scale, since the color differences are so subtle. Similar products seem to have the same type of scale, so it may be an inherent issue.