Rejutka recently mentioned this regarding the state of their filament...
So, I wanted to post a method on how to prevent your filament from becoming stale.
We purchased an air tight container from Amazon. It has weather stripping around the seal
With that, we purchased a safe dehumidifier. It is the rechargeable kind.
We put all of our filaments in there when we are done. The canister will have its first recharge this weekend (beads are starting to show green, so it may not need it, but we will anyhow). The canister has a clear window on the top indicating when it is time to recharge. The beads go from orange to greenish orange and then to green. Green indicates moisture and that the pack needs to be recharged. To recharge, you put it into an oven at 250F or 120C for a couple of hours. Then it is ready again and the beads will be orange. Simple but effective.
Here are some pictures.
Hope you find this useful.