Well, first you should know that I am brand new to this too. I have only had my BP for a month and I made every single mistake in the book. The folks on these forums set me on the right track. If I were you I wouldn't mess with an enclosure that's too big. I did the same thing and couldn't maintain temprature or humidity. Not to mention driving the poor snake crazy. Tubs are the easiest way to maintain humidity. But the right sized aquarium will work just fine once you have it set up right.

There are tons of caresheets here and they are all just great. Don't try to reinvent the wheel. These folks know what they are talking about. Another advantage to having the right sized enclosure without all that junk taped to it is that it is easy to clean which you should be doing regularly. Sounds like you have a 20 or 29 gallon tank there. How big is your snake? And How high is the tank? If your baby will fit in a ten gallon tank (see care sheets) they only cost ten dollars!