Snakes are the easiest animals to maintain in fully captive conditions (fully dependent upon their keepers). Corn snakes kept in a vertical rack system using plastic tubs with aspen or similar such substrate is the easiest way. Expect to scoop out a handful of substrate with the feces about once a week or so, change the water once a week, and perhapas clean entire cage replacing bedding only once or twice annually. On top of this, one meal every week or two (depending on size of food item, of course) is all that is required. Easy. One could actually work the animal a few minutes each week and keep it in excellent condition.
By the way, aquariums are commonly used, but large plastic storage containers are much better (with rounded edges in the interior). The aquarium is harder to clean and just a waste of vertical space in most cases.