That will work fine for your 30g though a bit larger would be better but it will work. I don't know a lot about the miracle mud or refuge mud, I have a deep sand bed in my fuge about 6 inches. (20g tank).
What you are going to want is to have some LR
rubble and some Macro algae. If you check ebay you can order some or if you would like I will gladly send you some of mine. The algae and the LR
Rubble will help filter your water.
Yes you will definately need a light for that tank. They should have one that fits it where you ordered it from.
Welcome to the world of natural filtration!!!