You can use any sort of substrate you want w/the riccia. It doesn't have any roots at all, and if left to its own, it will float. Anchor it down using some stainless steel (mesh or bent bars - do a search and you'll see what I'm talking about).
The riccia doesn't require root tabs since they're not root feeders. If you meant root tabs for the swords and hairgrass, by all means, go for it.