Looking at getting some sand here this week and looking at my options...Do I have to use aragonite sand or can any type of sand be used? I have a 30 gallon tank, roughly how much sand do i need for a few fish, soft and LPS coral?
Aragonite sand is not necessary, although I think it provides a nice look. Depending on the animals you want to keep, you might not need any sand at all. A 1" bed for looks should be fine, for that matter.
your sand base and live rock for the biological filtration for your tank. I would buy good quality live rock and a good argonite for the substrate. For a 30 gal the little bit you save might come back some day and be harder to remove.