1. I bought a test kit from Home depot and got a reading of 190ppm
2. Checked with my pool guy (who I want to get rid of and start maintaining on my own). He got a reading of 120ppm using his kit.
3. Went to a local store with a sample of water and they got a reading of 120ppm.
4. Suspecting that my home depot kit was bad, I bought a taylor Kit from the pool store and tested it multiple times at home.
Got reading of 170ppm,150ppm,etc..but not anymore close to 120ppm.
Not sure what I am doing wrong. Please advise.