I like the way you roll. I been using this setup for a while now. Two of the long flatter tubs. Some silicone sealant (waterproof) to put em together (take a razor and smooth to make that flat edge). and i cut a hole, then place a 1 inch long piece of pvc pipe (not wide...in length), 1.5 inch wide, seal that in there and it acts as a universal adapter to my humidifier. then cut a rectangle hole in the top and made a lid. theres so many ways i thought of, but just a square with the outline of the rim in sealant is easiest and it does nicely. so far i like it a lot.. fits under my bed which is nice.