that's not a good idea for a reef tank.
you are going to have a hard time lighting it.
i would just keep it to fish and inverts.
smaller grained sand would be my choice for the bottom. it's personal preference really, but the smaller grans require less maintenance.
- i believe once it's full of water you won't see the scuffs. they sell acrylic repair kits, but i never had any luck with them. i ended up making it worse.