How many lbs. of gravel?

[Heady]

How do you know what grade is what size when buying from a hardware store?

I would like a dark charcoal substrate if I can find it cheap. (Onyx is nice but expensive. Also it has just a little smaller size than I'd like.)

 

[Woozledad]

I went to Lowes (similar to Home Depot) and bought commercial grade, medium Sand bye Quickcrete.

I used the same stuff, came out perfectly.... But, I sifted out the smaller particles and used the coarse remains...50lb bag for about $3....Cheap enough....