I would assume it is 100% inert, but I wouldn't risk it. I used this sand and it works great and is 100% inert. hth Pool Filter Sand 50 lb. 26 in. H x 14 in. W x 4 in. L - Ace Hardware
Well, no, I do not mean round. I am a literal type of person and mean it's is intentionally graded to be jagged. AKA: sharp, rough, *angular*.
I am in the process of doing so now! I am ordering a bunch of plants next week & I can't wait! I am glad you found what you were looking for !
I agree with John it is odd.