I have been reading, as many of us newbies do, about different growing mix components. Is there anyone out there who can show me (pic) the product you use as pumice? I want to see particle size, texture etc. I have been using Growstone, an expanded silica product, which I have thought is a fair substitute for pumice, since I can't get the real deal in Michigan without major shipping costs.

Also, can someone show/tell me what "decomposed granite is? And how is it different from the granite I purchase at a feed store; chicken grit/turkey grit?

This is Growstone. It is somewhat porous and very light-weight.