alkalinity test

I have a like new, never used alk checker been sitting around for years. Just replaced the battery and works like it should. There is no reagent with it as it has long since expired. $40 shipped

I’m trying to use the alkalinity test with the Red Sea foundation pro kit, but when doing the titration the tank sample never goes from clear to blue, and never turns green either. after a while it becomes a pale ish yellow, but never turns blue or green. I’ve done it several times now, and I’m...

Hello, For sale is a GHL KH Director in black with extras. Usage Description A second wider gasket was used in order to prevent water leakage where the PH probe screws into the KH Director. An original gasket or screw cap can be purchased directly from GHL to fix the issue, but I was too lazy...