First off, how do I make an enclosure stackable? Are there certain pegs made on the bottom that fit into slots on the top of the other or do you just set an enclosure on top of another? Is simply putting on top stable? I'm also reading that having them stacked makes the temperature uneven, the one on top of the bottom one hotter and the one in the middle the hottest of the 3. My question is how do I prevent this? Can I put something between the enclosures to make them separately controlled again?
Take the bottom of the viv and make it 1/2" higher then the sides and the facia. And also make the back 1/2" higher then normal. You end up with a 1/2" gap of air space between the vivs and it looks like there is no gap. And if the vivs are built square theres no need for slots and grooves to hold them stacked. If your really worried about it get some metal brackets from home depot and screw the top of one to the bottom of the next.