Started typing this yesterday and got interrupted so if another post about this is floating somewhere put there, my apologies. Has anyone ever had issues with your master test, specifically the Amnonia part of it? Mine doesn't change color of the tested sample at all, as if nothing has been put into the test tube. I had my tanks tested this same day at lfs to double check and one of them qctually did have trace amt of ammonia so thus test is unreliable. I emailed the manufacturer but no response (ofcourse!) will try to call the 800 number customer service this am. Meanwhile was wondering if you guys ever had something like this happen since so many of you have recommended this test. Any input will be very much appreciated, thank you