This is a good read on how to quarantine a new addition:
http://ball-pythons.net/forums/showt...antine-process
As I think you have discovered, adding a second ball python is just a stepping stone to adding six ball pythons. Tanks are really not the way to proceed from here, no matter how much you like looking at them.
Multiple tanks lead to multiple problems for space, cleaning, and husbandry. I really urge you to look at something like this:
http://www.reptilebasics.com/iris-sw...y-or-back-heat
Once you go rack, you'll never go back!
And, as an added bonus, a rack is not nearly so conspicuous as a bunch of 20 gallon longs in your living room. Your landlord will be none the wiser![]()