ok so i have a small store bought python and i have her in a big 40 gallon tank... i was told that a 10 - 20 gallon would suffice and that a 40g is too big.. =/ she has lived in it since dec or jan, but no problems have come up. the vet pic was just a checkup (since i bought her from petco and i dont trust them). i was wondering if i should buy a 10-20 gallon tank and move her there instead, or would that cause too much stress? if i DID move her, i would have to adjust heating of the tank, so if theres a heat/humidity/husbandry guide for setting up a smaller 10-20 gallon tank.

picture of snake to show size(after vet checkup):
http://img39.imageshack.us/my.php?image=img1390.jpg
picture of tank to show size (old pic; made a few more purchases):
http://img39.imageshack.us/my.php?image=mypython.jpg