I have a SSSF, when I switched to the larger tank this was one of my concerns, you can drop or even bury some pellets (use what ever size you think is suitable) in the sand that should help the SSSF, as for the nass snails, they should be fine, but you can give some shrimp to them once a week if you want, just watch them to make sure it's all eaten, but if you have hermits they'll take care of whats left.
Mine is still alive and kicking, TBH I see less of it now than I did in the smaller tank.