So our PB says that we have to have a pool store test monthly for the plaster guy to warranty his product. Which is not a huge deal. So with me using the TFP method my numbers are great, which I knew before we took the water sample in. From what I have read when your numbers are good the store goes to the Phosphates test to try to sell you something. the test says we are @ 500 ppb. We have a bottle of phosphate remover that the PB gave us when the build was finished. Is there any harm in using it if I cant return it or should I just give it to a neighbor that will probably need it due to using only trichlor to sanitize their pool?