I've been planning to build similar. It would be very easy to build a frame out off 1x4 lumber. Built like a house except the weather proof is inside and the pretty is on the outside. Line the inside with 1/4" pvc sheeting. Running heat tape through an opening left in the 1x4s . Th 3/4" gap between tanks caused by the 1x4 would allow the tape to breath well. Once the inside is made like this you can cover the outside with whatever you would like to make it look nice. Sheet rock it to blend in with the walls except for the glass doors, or use wood of your choice to make it look like furniture. Sort of like building a 2x4 wall, you can put a layer of insulation between the pvc layer inside and te external finish layer. For a 12"x 24"x48" it'll cost about $100-120 for each level of the tank from just a quick search for materials. Mostly due to the high cost of the pvc. The wood framing is cheap. And the outside coverjng is as expensive or cheap as you want to make it.
Kyle
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