Join Date: Aug 2011
Location: Kingston, Ontario
KH is carbonate hardness. CO3 is carbonate, often bonded to calcium, yes, to produce CaCO3, which is the essential component of every invertebrate's shell. KH directly affects pH.
gH (general hardness) is the measure of minerals, namely calcium and magnesium, but others (such as sodium) also come into play here. This is totally independent of pH. You can have pH of 8 with kH 200ppm, and gH of 40ppm, it does happen in the wild.
In greatly acidic waters, freshwater snails can have their shells dissolved, the water drawing out the carbonates from the animal's shell. More common in a too low pH though is the invert simply cannot grow, and often becomes weak.
Many nerite species are found wandering around in acidic waters with unreadable calcium levels in the wild, I remember reading. This is the best snail for an acidic tank, I am not sure what is going on here but I don't think pH is affecting this snail at all. A calcium supplement never hurts, though.
taking a break from fish-keeping.
3 lovely male betta still keep me company.