he already stated that he is using liquid kits, not strips, and since he has gotten results with the tests previously, he obviously knows how to use them.
yeah, just keep testing. keep us updated. maybe take a sample to your LFS and get them to test for nitrates, maybe the problem is with the test kit itself.
yeah, just keep testing. keep us updated. maybe take a sample to your LFS and get them to test for nitrates, maybe the problem is with the test kit itself.