Yeah, the reason most rocks cannot be used is because of their mineral make-up. You need a non-silica based rock. This is the reason that calcium carbonate rocks, such as aragonite or dolomite (i believe) are used as substrate and base rock.
Evan.
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40g with 10g sump with 40 lbs liverock, 1.5" deep livesand bed.
Fish - halloween hermits, blue leg hermits, left-handed hermits, emerald crabs, assorted snails, chocolate chip star, 3x strawberry conches, tuxedo urchin, electric flame scallop, gold stripe maroon clown, carpenter's flasher wrasse, 6line, yellow tang, yellow watchman goby, white seabae anemone.
Coral - Yellow polyps, Kenya Tree, Purple Acro, Pink Birds Nest, Hammer coral. | 
Non-aqua rock as base rock? 
