Does live sand act as a PH buffer, or is that only crushed coral that
does that?

they both could, however neither really do.

to get good buffering out of either your tank ph has to be LOW, you can search
groups.google.com for past discussions(look for one from boomer.) but i think for real
buffering the ph had to be in the low 7's. if your tank ph is that low, you have other
issues besides CC or sand.


--
Richard Reynolds