I'm planning to set up an aquabag in the backyard, since it's water resistant and won't get moldy. But the chain, spring and everything needed to hang it up is made of metal. Won't this rust? If so, do you guys recommend building a little roof to keep it dry? Or will the humidity of the rain itself cause rust anyway? How much will a rusty chain/parts impact the aquabag? Or will it still be fine? Any tips? Thanks!