I would set it up as an African cichlid tank. Vary little cost to this. They will also mouth breed constantly right in the tank. Vary cool to watch.
You can use regular old treated tap for water. Any substrate you like and flower pots and cheap sand stone to provide cover and just basic cheap flourecent lighting.
While you will have to provide some water movement but it will be nothing like whats needed for sw tank. Filtration is not as important as long as weekly water changes are performed along will some substrate vacuuming.
Introduce and odd number of juvinals and you will eventually end up with one male with a harem of females. Or possibly two competing clans give the tanks size. Melanachromis(sp?) were my favorite back in the day.
Shhhhhh. Dont tell any body but there are days with my reef tank that I contemplate breaking the whole thing down and going back to my cichlid beginnings. My wallet sure would thank me for it if I did.