I have always just looked for nice shapes and not worried about what kind of rock it is. Go to your LFS and start pulling rock out of the holding tank and see what feels right.
IMHO that is the only way to do it.
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- Greg
90G : Light - Tek 6xT5 | Skim - EuroReef RS135 | Flow - 2xVortech MP40W | Control - Reef Keeper 2
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