Perlite has no internal porosity. As a consequence, it holds much less water than Turface. on a size for size basis, perlite is closer to a substitute for granite than Turface MVP/Allsport.

Perlite holds much less water than Turface and considerably more water than granite. Particle size is important, so you would probably have to have found the course horticultural grade of perlite for it to be suitable as a sub for granite.

Where do you live? You can substitute NAPA floor dry for Turface if you have to.

Al

Al thanks for the clarification. I must have read that post wrong. Yeah, I didn't think that perlite was very water retentive. I have the Turface or the NAPA floor dry available.....or even the Carquest floor dry. Anybody ever try the Walmart floor dry? I was hoping that I could possibly avoid buying ANOTHER large bag of stuff. Well, I gusss there's always room for 1 more bag. Thanks again :-)