Found an acrylic box the same size as an eShoppes one and used gorilla glue and aqueon silicone to seal all sides! Also found an ACTUAL eShoppes overflow box in my garage for no apparent reason and used it to make the weir.
Yep! My build thread is the tank fully run for about a month now. No leaks besides the time I accidentally clogged it with some really really thick sponge for no reason and it blew up, but nothing gorilla glue couldn’t fix!