Not to throw this thread off, but in my opinion, depending on what is in the tank, 400 may be OK. I agree with the
ALK, MAG, Calc stuff, but maybe we are fixing what is not broke. My tank for example (mainly a softie tank) runs through very little Calcium. I was running
Kalkwasser a bit and noticed that if I kept religious with my water change outs, that the calcium remained between 400 and 450 for the most part without any
Kalkwasser.
