why aragonite?

[Flear]

that's a difficult read.
yup, i remember coming across something somewhere that mentioned ammonia vs. ammonium. granted i payed more attention to the ph where it concerned optimum nitrate cycle.

they mentioned a high ph for ammonium is fine and dandy, but if your ph drops the chance of a catastrophe as the ammonium gets converted into ammonia likewise goes up. maybe it's unfounded fear, maybe all truth, with that in mind though i just decided to stay clear of the thought of excessive high ph (and the fish that want the high ph.

if ammonium does not convert though, all new ammonia that is produced does not have the required beneficial bacteria to deal with it, like cycling a new tank, only now it's fully stocked.

personally, not likely to happen in a reef tank with how hard the water is, change i'd think is very slow, but i'll still try to stay clear.

then again corals will try to strip the calcium out of the water, which could cascade in a domino effect (resulting in softer water and lower ph), hence the reliance on aragonite to keep things in check. as the water changes the aragonite substrate is dissolved back into the water column.

and the two kinds of calcium sources and how they react to different ph's, one dissolves at under 8.2, the other at over 8.2

honestly i don't know, maybe i'm spouting nothing real, i'll look into it more seriously to verify when i set up such a tank

 

[Flear]

Khemul.
all the buffering comes from somewhere, ... the harder the water, the more locked in the PH is, the harder it is to change.
water has no buffering capacity on it's own. all the dissolved solids (and other chemicals) that set the PH through their own natural PH, and increase the hardness, making it harder to change.

for PH neutral dissolved compounds that just add to the hardness, better have your PH adjusted prior or you require a lot more of whatever your using to set your PH to desired levels because you didn't set your PH at the start.

"buffer" (i think) is just a term for things in the water that tend to keep it at a set PH. it's not a natural function of the water itself, water is naturally 5.5ph. dissolved solids (even from rain as it falls through the sky) bring the PH to a neutral 7.0