Why not get a 100-300 gallon Rubbermaid stock tank? Much cheaper and if someone says there's some issue with the type of plastic you could always use a pond liner, that you'll need for the pond later anyway, so the water wont come in contact with the container. I don't know how big they get but do know they have 300 gallon.
You dont need a liner with Rubbermaid stock tanks, alot of monster fish keepers use them. You do need a canister, a wet/dry, or a DIY filter however.
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