Our snakes have a new home in a 20 gallon viv (yes, they are together for right now, I've gotten the lectures
How about another lecture?
Perusing through your threads, I have come the conclusion that you currently own 2 aquariums: a 20 gallon and a 10 gallon. Therefore the snakes have the capability to be separated. Both tanks have their own heat supply, the 20 gallon the UTH, the 10 gallon the side-mounted something I've never heard of. So why aren't these unsexed and now mite infested snakes separated?
Instead of having just one snake to treat for mites, you now have two. So if you get one cleared up and the other still has a gravid mite remaining somewhere, its going to re-infest the whole lot. This is one of the main reasons for housing separately, disease and parasite transmission.
If money was the issue, you wouldn't have been able to go out and buy a whole new complete set-up for them, nor the mite treatment, nor the snakes in the perfect world. Because they "look pretty together" or "because they seem to like each other" aren't really a valid excuses. Frankly, I can't think of a single excuse to validate keeping animals together that don't really like to be together in the first place, other than selfishness and laziness.
The added stress from having to harass your snakes by continual cleaning, de-miting their bodies and already seeming to be fussy eaters might just compound the issue into a whole other monster. Please separate them before its too late.
After reading everything, I also didn't know that getting the heat-cold ratio in a tank was THAT hard. I like a cold house, and generally I use only a UTH or a lamp, but not both on the same tank (unless its my BP tank who needs higher temps). I think you're just making a mountain out of a mole-hill. These are temperate climate snakes, not something that needs exact temps. General and slightly above normal room temps make them happy.
Then again I'm not particularly picky about it either. So long as the general overal temp stays above 75, I don't worry. During the day the light or UTH is on, at night its turned off and voila, daytime high and nightime low. Most of my snakes now are in a room that's kept a constant 83 degrees. No stress from it being too hot or too cold, no regurges, everything as normal.
The wattage on your bulb sounds a bit much. I don't use anything above a 40 if I can get away with it, especially if its a black or red bulb that's on at night. So that may be why you can't get your temps to drop at night. Besides, snakes can see the black/blue lights, they really can't see red so it doesn't disturb them at night. If you must have a light for display purposes, use fluorescent lights. They put out virtually no heat at all.
Steps I think you should take:
1: Get your snakes sexed by a qualified person
2: Separate, Separate, Separate
3: Treat them for the mites
4: Keep their enclosures super clean till the mites are gone
5: Don't become anal about tempreture gradients, that's the perfect world and most of us are happy so long as they stay within 75-82.
Since I'm certain that we will be getting atleast one more corn, I was going to go out tonight and buy a 20 gallon,
I hope that is still not a goal for you under the current situations. And if it is...
I'm starting to sound like a broken record, and wonder if I should even own snakes...
Then I'd be inclined to agree with you..
Sorry if it sounds snotty, but this just really annoys me when people KNOW the dangers and ignore them anyway. You seem to genuinely care about the snakes' health and well-being, but yet you put them into known dangers.