What temperature is your snake's cage with the heater? Your room temp sounds fine to me, but heat gradients are still good for snakes to have. If your heater isn't pushing the temp up too far, go ahead and leave it on. (They don't use much electricity.) If your house temperature is always a constant 78 degrees and doesn't ever get colder, you might be able to do without the heater during the day, too.
Amelanistic and albino are synonymous in the cornsnake world. So yes, an amel is an albino. They're also often referred to as 'red albinos'. 'Black albino' is sometimes used for anerythristic corns.
-Kat
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"You keep WHAT in your freezer?"
"Mice. And rats. If that bothers you, I can call them 'cows' instead."