RR-MAN
Supporting Member
Good point but it's very difficult to maintain a tank with kalk alone.
kind of depends on what your source of alkalinity is...
Na2CO3 sodium carbonate (soda ash) ph 10.52
CaOH calcium hydroxide (kalk) ph 12.4
so using kalk over soda ash will provide a little more ph bump over regular 2 part..
but if you want a larger ph bump use NaOH sodium hydroxide.. ph >= 14
Reef2Reef: New DIY Two Part Recipes with Higher pH Boost