Not technically Rubbermaid, but here is what I am using.
30 gallon from Wally World Including the lid. (Less than $10)
The fuge is just a square plastic trash can that fits inside just below the rim. The handles on each side work as overflows.
(Less than $5)
FYI - If you look I had to cut a slot in the back of the stand cause the bucket was too wide. to close the door. I drilled a couple holes and used two screws to hold the cut out (euro brace) lid in place (in case of power outage)
You can't see through it, but I prefer this thicker bucket better than the thin see through buckets.
They have bigger ones but they would not fit under my stand, so make sure you measure your stand,
Drilled one hole in the bottom right side for a bulkhead to the return pump, cut the center out of the lid, and drilled two small holes in the lip to secure the lid in the front.
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