reeferkeeper420 link said:
Have you done any double or triple tests to see if it gives you the same reading everytime jroovers?
I've never read anything over 0.03 on my phosphate checker, and that is with repeat testing (i.e. it was within source of error consistently between 0.00 to 0.03, as I think the SoE is 0.03). I lent it recently to Tyler and I know he got some different readings on his two separate systems, which is expected, and I think he said they were 0.00 and 0.10, and I know he was planning on doing some repeats as well so I'll check with him and see what he has found.
My alkalinity checker seems pretty consistent. When I've had alk below 7 dkh after using the multiplier from ppm, I've re-tested and it has been within a few ppm on re-test, which is negligible when converting to dkh.