Just checked out this thread. Super sweet!! We made the mistake of using the same racks for some of our 40b setups and the 2 longer bars ended up splitting even with 2 layers of 5/8 inch plywood and the plywood dipped in the middle. We ended up having to drain the tank, lift the plywood back in place and used bar clamps to keep the 2 bars together flush against the board.
With good insulation, once the water temp reaches certain temperature, the room temp will stay fairly constant but keep humidity in mind. We had to deal with mold after a couple weeks. Even with lined walls, all the water collecting will get gross. Definitely invest in a good dehumidifier to keep humidity low while keeping up temps. Covering your tanks help a lot as well but not sure if you'd want that.
Looks like an amazing project and have fun with it! Don't let it become too much of a business, it makes it much less fun in our experience.
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