I've never seen sand ina frag tank, but I've seen live rock in the sumps of frag tanks. Im sure you can add rock rubble if you want. But you definitely don't have to by any means.
I've never seen sand ina frag tank, but I've seen live rock in the sumps of frag tanks. Im sure you can add rock rubble if you want. But you definitely don't have to by any means.