Originally Posted by Ray01
Has anyone used an expired test kit before? I'm asking because I ran out of strips and have the API test kit laying around. The most expired bottle expired 01/2019 and the least is 03/2019.
In my experience, the Ph test chemical works for a long time even after expiration
The Ammonia and Nitrite test chemicals will last slightly longer than expiration.
The nitrate test chemical is what goes bad the quickest. I've had many of them give false readings even before expiration.
I would suggest taking your readings with your chemicals then have your LFS
test your water to see what they get to compare. Then you will have a better idea whether your chemicals are working correctly.
That said, I would not compare the liquid tests to the strips. Strips have a bad reputation of being inaccurate. I would suggest using the liquid API tests.
Hope this helps.