okay phew, just making sure.
Silver dollars are herbivories and vicarious plant eaters, they are also schooling, more skittish and quite large. I have 5 and love them but they are definitely hiders..
You could try it if the plants you keep arn't normally on the diet plan of the silver dollars
What about a school of tetras or rasboras?
They will give your RTBS no trouble on the bottom and should hang out more in the middle zone as to not disturb your gouramis too much...