Mjolinor, that's the first mention I've read bout using a separate container for the dirty water, such great ideas are flowing (intentional pun). My friend Aragon proposed the save louvered cone that you describe, which I feel is a great alternative. Ahhh how about we discard the bottom half of the 2 liter bottle and use a glass jar there. the glass jar can hold the dirty water and be painted black for heat reasons. hmmm or the bottle could be upside down with the top cut off of it. In both arrangements the thing that is printed, which must be small to be cost appropriate, is just a planar disc with details. keep the ideas um flowing!

Les