barimetric preasure also adds to it, you would think when a high preasure fronts comes in you would loose more, IE drier air, it is the opposite, low preasure it evaps off easier, I loose more here in Wisconsin in the spring and fall then I do in winter, dry, and in the summer with the AC on, spring and fall I loose 2 gal a day, tank is covered, but a computer fan on in hood when the MH are on for 8 hours, winter and summer same lighting time but I only loose a gallon a day, go figure!!!!!!!!!
If you want to retire early, do do this hobby!!!!!!!!! Electric bill doubled with my system!!!!!!!!!
Bob