You can snake one length of tape thru the rack and only need one connecter. Unless you wanna be able too stop heat to one tub or think the added side heat would be too much. That's how I'm going to be doing mine tho cuz winters get cold up here ha
Normals 1.3
Spider .1
Carpet Python .1
Dog APBT .1
Reptile Basics has plugs, clips, and insulator sets combined and they will even connect it for you for free if you want. If you set up each shelf with its own heat strip and plug, then if you aren't using a level, you can simply unplug it from the power strip you have plugged into the thermostat. Saves energy and dont have to worry about failure of one connnection effecting multipl levels.