Windshield Washer Fluid Reservoir level

[romram]

everytime i fill up my 2010 yaris Windshield Washer Fluid Reservoir,
i find it after a few hours, the level is always at bottom neck. are there any overflow outlet that discharged the excess? also how does this container connects to the rear windshield wiper?

http://s157.photobucket.com/user/romjedd/media/IMG_4875_zpsyvbnjwnf.jpg.html?sort=3&o=0

http://s157.photobucket.com/user/romjedd/media/IMG_4874_zpsorpaexuu.jpg.html?sort=3&o=1

[Exiwolfman]

That is normal do to air trapped in btle as the car sits air escapes level goes down.... Anyway that is my theory lol
Rear is connected by a tube that runs to the back powered by a electronic motor u have two one for front and one for rear both located at the base of the tank.

[xdarkxfirex]

Same problem on the 08 we have. Couldn't find a leak, turns out it was the cap. The back usually doesn't close properly and the methanol evaporates in it.