Red Sea NO3 kits - Regent A
Recently my test kit appeared to stop working. If you have one, you have noticed in the instruction to shake regent A very hard for 30 seconds so to get as much of the cadium dissolved (grey solid on the bottom).
I never remember getting all of it to dissolve, but the kit worked fine then. I didn't use it for about a month but now it seems theres a lot more grey stuff on the bottom. And now it reads 0 after a dosing of KNO3.
Anyone experience the same?