I just had salt added to my pool. My question is, should I get a salt testing kit?? I have an Aquapure system and it gives me a salinity level, but something is wrong with it. It is telling my I have a high reading over 4.0 which couldn't be right. I did take a sample to be tested and it was 2700 ppm. So, I don't trust the system at all and think I should get a test kit. What do you guys do and use?