Water testing questions.

[Sandy Clay]

Ok, I bought a new Nitrate tester. Had previously used API. My nitrates from the faucet were around 50ppm for both. So....I contacted the water company and they tested my water ....it was 7.2 ppm. What am I missing? I have tested this water numerous times and it is always high! Experts?

[pcsb23]

Hobby test kit? If so there is your answer, they are rubbish as a rule. The water company will have used lab grade tests and reagents.

[Sandy Clay]

I guess the thing I am confused about is....If these test kits are not accurate, then we are wasting A LOT of time changing water, when we don't need to? I have two different tests and they read about the same. I do 50% or sometimes more once a week on a 75 gallon. I was freaking out about this nitrate thing and then after testing my tap...I thought oh, ok, that is the problem. After finding the nitrates to be 7.2 from the water company it makes me think the nitrate test kits I have are junk. One you have to shake the bottle for a minute, the other not at all. Oh, well....I'm am going to relax and enjoy the fish