Tom Barr;13270 said:Gievn the wide variety of user error in KH measurements, I've asked Greg at SeaChem if they might be so kind to make a reference KH solution that is accurate to less than 1ppm for the hobbyist.
Ok - I made the 4 dKH water test solution and the test kit (Hagen) did measure pretty darn close... at 7 drops it was almost color changed - you know when you hit that stage when you can tell with 100% certainity that the next drop will be the one... and 8 drops did it.
So my kit tests the 4º solution at between 3.92º and 4.48º KH - to me thats good enough.
So getting back to the origional reason for the thread.. something has dropped my KH from about 100ppm to less than 10ppm in my tank... this in turn now keeps my pH down around 5.5 and my GH has remained relativly unchanged.
Still open to any suggestions as to a good course of action to get this back on track?