You can pick up an acurite thermometer/hygo. from home depot or wal mart for about 13 bucks. they make it really easy to read temps and humidity. also you should get an under tank heater and a dimmer so you can turn the heater down since they can get well over 100 degrees and you only need it to be between 92-94, the lamps tend to suck out the humidity from your tank. I would just keep one of them in the 20 gal and make sure its kinda cluttered up so the snake feels secure, eventually the snake is gonna be big so why spend the money on 2 10gals?? I would get another 20 for your snake and keep a 10 gal incase they ever refuse a feeding (i feed live) unless you feed f/t then forget that. Good luck with your new babies they are really cute