[serpentman]

To the best of my knowledge, any method would end up closing off your tank. The only way I know is to condense the water vapor like a distiller or dehumidifier. However, it would not be energy efficient.

What is you motivation for reclaiming evap, humidity or water loss?

For humidity, you can vent the room or use a dehumidifier in the winter (which really shouldn't be an issue due to the low humidity heating your house causes). As far as water loss goes, setting up an ATO is a heck of a lot less work than it sounds like.