Algae in the air?

[DrNic]

I have a vase with some 'lucky bamboo' and a few vines growing in water near one of my windows. Overall the plants do fine with just water and some hydroponic plant food I add at the first of every month. This month however I noticed something strange, much to my surprise for the first time there is algae growing in the vase. I haven't added any water to the vase for over a month and I know that 2 weeks ago the vase was crystal clear (I took some photos with it in the background). We do keep the vase near a window however and it has been stormy and windy here a LOT this month.

Can algae move through the air? I can't imagine how else it would have gotten into the vase.

[Nautilus291]

Algea lies dorment in water, so being in the window with the sun on it would help it grow. Also it's probibly getting it's food from the during plant matter, which could be the reason it took so long to form