Time for a bigger hidebox: parts of the snake stick out. nice 'n simple.
Time for a bigger tank: snake is more than twice as long as the tank. However, balls don't move much, so the biggest you usually need is a 30 gallon, maybe a 40 if you're concerned. Most breeders keep their snakes in plastic tubs that you can buy at walmart, so a 30 gallon is usually adequate.
Like claude said, just splurge and give the snake more hideboxes. I use cardboard boxes for my snakes. My boy loves cereal boxes and my girl does great in shoeboxes, and my baby recently upgraded to... feminine product boxes. (some friends of mine who hadn't seen my snakes in a while burst into laughter when they saw my baby curled up in one of those)

~jenny
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1.2 normal ball pythons (Cindy, Darwin, and Periscope)
0.2 rescue chinese water dragons (Yoni and Linga)
1.0 rex rat (Scurvy)
1.0 gerbil (Yerbul)
0.1 bunny (Spazz)
1.1 betta fishes (Vicious and Killer)
2.2 great danes (Shasta, Odysseus, Merlot, and Watson)
1.0 fat fuzzy mutt (Smokey)
1.1 cats (Thidwick and Turtle)
3.0 horses (Buddy, Sam, and Scout)
1.0 goat (Billy Jack)
1.25 chickens (Ugly the rooster and his harem)
