Thanks! It was the "R" that had me baffled, no pun intended. I guess I'll just run live rock in my sump and call it good. The base cabinet for my tank is already full and my wife wouldn't like a 5 gal bucket sitting in the living room.
Well that certainly was informative. I was acctually planning on useing the sand bed with some live rock to build a pod pile with some cheato floating on top.
As an alternative to a bucket, you could use a 10G tank and make a small stand for it so it is a little above your sump level so it can work via gravity. If you could drill the 10G towards the top for the overflow to your sump you can have a very nice external RDSB and plant some nice Mangroves, live rock rubble, cheato, and make it into a full blown refugium that can be its own display. You can even put little critters in it to make it its own type of tank to watch and enjoy.
Some people use a RDSB because they want their main display tank to be barebottom, no sand at all, but still want the benefits of sand.
If your planning on putting sand in your display tank then I would skip the sand all together in the sump and just go the rock rubble/cheato route. Unless your only planning on 1-2" of sand in your display. If your planning on going barebotton in your display then I would still make that area into a DSB because like FSN77 said, any DSB is better than no DSB.
I am planning to have at least a 2 inch bed possibly 3 in the DT, and I know I want a pod pile somewhere, so I think some small LR, not really rubble, and some cheato in there will do, but Im open to suggestions.