Where did you get the LR
from? Ask the source and you should know. Caribean rock is less porous than Pacific rock so it weighs more, but doesn't have as much surface area for the bacteria.
As CaptainAhab said the guidelines for LR
are actually pretty accurate. You can get by with less weight of pacific, but you should still maintain about 1 pound per gallon for a FOWLR
tank and go for the 1˝ for a reef. I have about 185 pounds of LR
+ 15 pounds of LR
rubble in my 125 and sump and the fish have plenty of room and hiding places.