Posted: Sat Nov 22, 2008 3:23 pm
Does the room have windows that aren't allows any cold air to seep in around them even though they're shut? If so, you could get one of those kits that contain a plastic sheet you attach over the window to provide an extra layer of insulation against the cold (you won't be able to open the window unless you remove the plastic).
If they absolutely must stay in the room, and there are any drafts in the room, make a barrier around the outside of the tank where the basking area is to help contain the heat (will help even if there isn't a draft).(What's the basking area temp? Is there also a UVB light?) If the tank is at least a 50-gallon one, you might consider a mercury vapor bulb (T-Rex Active UV Heat, Mega-Ray, for example), which give off good heat and also provide UVB and UVA rays.
Is there good filtration to circulate the heat from the water heaters (what kind and wattages are they?)
My turtles are all in rooms that are very cool (including the basement) I keep at least half of their tanks covered with a sheet of plexiglass during the day to help maintain the warmth in the tank and keep up the ambient air temp. At night, when lights are off, I cover just about all of the tanks with sheets of cardboard.
You can also keep the warmth in the tank by putting something under it for insulation and also wrapping it with something (a blanket, towels if it's a smaller tank). I use stock tanks, so this is not an issue, it would be more difficult with a regular tank on a stand.
If your turtle are not hatchlings and are healthy, you do not have to raise the temp all that much, especially if they're used to a cooler temp. My adult RES is doing fine with the water temp 68 - 70F, but he's used to cooler temps.
Aside from upping the temp, it's important to keep the ambient air temp from getting too cool. (Even if the water is warm, breathing cool air can, over time make them ill.) Covering the tank, especially at night when lights are off, will help in this regard. With hatchlings/smaller turtles that are in cool temps, I've also used red heat lights at night (I'm doing this with two tiny snappers currently), which just warm the air but don't provide light. Some people have also used ceramic heat emitters.
"You become responsible, forever, for what you have tamed." -Antoine de Saint Exupery-