Some filaments (materials) such as Nylon are very sensitive to moisture. We highly recommend to at least put used filament spool back in the original package (bag and box) with the dessicant. This is to avoid exposure to air and moisture. Our customers have repeatedly say that it works great.
You can also store used filaments in any humidity controlled container if possible. Some users have creativity converted a plastic storage box with lock into a good dry box for filaments. Checkout the video clip below.