As an alternative to large desiccant packs there are dehumidifier containers, for the lack of a better term, that are available from most discount, dollar stores and grocery stores. I don’t know how they work but they really do. The “pack” has some white beads on the top layer and an area for water to collect underneath them. I store my filament in a large plastic sealed-ish bin with one of these dehumidifiers in it and after about two months there is a noticeable amount of water collected in it. Best of all they are readily available and cheap.
If you already know about these then just ignore this.