I personally don't like anything on the substrait so I build pedistals out of PVC covered in cement.
This one is about 6" high and was built to house a gonopora. In a few weeks some coraling will grow on it and you will not be able to tell it from Real rocks. Actually, some of it is real.
I got the gonopora up on it's new pedistal
Here is the thing in the building process
And here it is on the sand.
