Can you check with the Mill and verify what you bought was made from the Bark - and not the core wood. Reason is that the core wood contains resins, and other bad elements that could actually harm the plant.
For larger quantities of Perlite, go to either a full service Nursery for a 2 cubic foot bag ($10.00); or better yet, go to a Hydroponics Store (ALL of them sell it) where you can get the cheaper stuff at about $17.00 for a 4 cubic foot bag.
I am worried about the wood chips you used.
Raybo