Hi all, nearing the end of the cycle on a new tank. I have a Hanna Nitrite ULR tester that to-date won't give a reading as every test reports '200' (out of 0-200 ppb range). My Red Sea Nitrite tests are coming in between 0.5 and 1 ppt. I believe I should trust the Hanna (non)reading, but that's quite a difference, no?