Originally Posted by TheLordOfTheFish
I keep hearing both sides here and can't make up my mind. KH at 0 is ok then for a heavily planted tank for the plants? I wonder if I should dose some extra K to make sure I have enough.
kH does not = K
K = Potassium - Plant macro nutrient
kH = Carbonate hardness - "measurement" of CO3
Aquasoil buffers kH out of the water and "stores" it thus lowering pH.
Tanks with inert substrates use kH as a buffering "agent" to prevent non-CO2 related pH swings.
Tanks with aqua soil can get away with no kH because the substrate buffers the water and prevents non-CO2 related pH swings.
By dosing kH into a tank with aqua soil, you'll be "fighting" the buffering ability of the aqua soil, eventually depleting it to a point where it will act like an inert substrate (in terms of kH / pH).
Plants typically do better in soft water .... low kH....
= Aquasoil tank or
inert substrate with a low kH.
Correct me if I'm wrong ADA soil users, as I have not personally used it before....