I don't see any problem then. Like Brett said, detritus can accumulate in there - but if you're looking after that, should be good.
![#smile](images/smilies/icon_smile.gif)
I would advise against putting any LPS on that kind of substrate. It could irritate their membranes.
Soft corals such as leathers would probably be alright. If they got too tall though, they would probably tip over.