GRF 4.5-9.0 Clearly Read and Accurate Testing Ph Test Strips with Free Alkaline Food Chart Inside

My husband and I bought these to help in our journey to be healthier. After reading a review that a strip with 3 colors would be more accurate, we decided on these. I have attached two pictures, here is what you're looking at..The first picture is of the results from my fish tank. The test in the background is from my API freshwater master test kit and the strips are the GRF test. *Now GRF does state that this is only for saliva and urine* but the 2.5 difference is surprising. Overall, I do believe my saliva results are fairly close at least.In a different review I saw that someone had said their test results were all the same no matter what they tested, this second picture is to show the difference in the results. The first strip on the left is a saliva result, the middle is the result of my fish tank, and the right is an unused test strip.Hopefully this helps with someone's decision to purchase these. :)

According to the color chart, the strips 'start off' at around pH 4.5. Putting them in distilled, deionized, or even tap water, they don't change to the 7 color. Or any change. Adding phosphoric acid to water that should be close to pH7, the strips never react. Thus, they are useless for my application - which is checking the pH of water with a varying amounts of phosphoric acid added.I _can_ get them to change using, say, NaOH, or even a standard reference solution - the type you use to calibrate a digital pH meter. But looking at two strips, one testing tap water, and one testing 4.01 cal soln, they are almost indistinguishable.I don't know why they don't measure the pH of water, and don't care, because that's what I need to do.Photo attached - one of these was in roughly pH 7 tap water, the other was in pH 4.01 cal soln.

At first I couldn't get a descent reading and thought they didn't work. When I used my own food/intake research and changed my intake I finally got a uniform legible result. Now I add a little lemon and baking soda to my filtered water periodically along with cleansing foods. However, it does dehydrate me...so when my schedule and location allow.

These are the best test strips i've used and i've tried a few. They are the most accurate in terms of matching the color of strips and ph indicator chart. At the price, quantity and quality you can't go wrong.

accuracy compares well with other brands I've used. Easy to read by matching the closest 2 colors. Nice product!

Very helpful and easy to use

There really isn't much to say about the product other than it does what it is supposed to do. Test your pH. You pee or spit on it and compare it to the colors on the bottle.

Fast shipping. I've tried many other brands from amazon. This seems to be the most accurate of the brands