That's not what the OP was asking. But anyway, Hatchrite is not perlite, you can reuse it indefinitely, and it's fool proof.
Hatchrite is perlite and it is not foolproof. I know a guy that let all of his eggs die because of the "no need to add water". It is a money making name to take advantage of people that don't know any better. I have perlite from 5 years ago. Rinse and reuse indefinitely.