When I first started in the saltwater fish tank hobby (1985), all tanks (that I knew of) had crushed coral as the normal substrate. Eventually, as time went on tanks have turned sand based and now sand seems to be the norm for FOWLR. However, now that I have stepped over to the coral reef side of the hobby I am starting to wonder if crushed coral is a better suited substrate (less sand turbulence when using wave makers). So with this I ask "What do you long term reef keepers use? and why?".