Its becoming summer so I would not worry it does not get so cold at night ..

SO would move them back into your care and dont worry if the power goes off for a couple of hours it comes back on :laugh:

@ marula: Humidity is defined as the amount of water vapor in the air. I was thinking less heat, less water vapor being absorbed in the air. Because of the cold there will be less condensation and less water molecules in the air.
I could be wrong but even though your tank could be nice and wet if there is no heat present the humidity wont change much.
This causes a drop in humidity in winter.
Just some interesting facts.

Wynster,

Absolute humidity: Amount of water molecules in a body of air.
Relative humidity: Amount of water molecules in a body of air at a given temperature.That's the one that matters in this case!

Condensation is not directly linked to humidity. It occurs in two cases:
1.: When the air is saturated with water molecules at the given temperature (100% relative humidity).
2.: If an object is colder than the surrounding air (think beer bottle or the walls of a heated T'enclosure in a less heated environment).

Condensation does by no means necessarily indicate a high humidity in your tanks. Actually, you mostly will need to worry about your humidity once you heat them up with heat pads and the likes. Condensation will offer your T's the possibility to drink from the droplets, though.

The air in a tank with 70% relative humidity will get drier if you heat only the air of the tank up. If the substrate is dry and does not supply water molecules to the air to compensate this by evaporation, the T' will battle with a lower humidity. The relative humidity will drop. If the heat source is close to some moist substrate, this will speed up evaporation and help to compensate.

If you lower the temperature inside the tank you will at a certain stage notice condensation because the air's ability to carry the water molecules drops with the temperature. No issues with a low relative humidity there.

Even the deserts regularily experience some condensation during the cold of the night.

:blink: Hope this helps to clear things up...

Thanks Marula for the great explanation.
I was on the right track, but just didnt have all the right facts.
Please excuse my bad english in the previous post. I meant evaporation, but instead said condensation. Im afrikaans and sometimes struggle to express myself properly. :S

Only a pleasure, you had it almost right!

Wynster wrote:

Im afrikaans and sometimes struggle to express myself properly. :S

I'm German and also trying to do my best with English being my second language