Never...ever...use WATER to wash off your stained glass project. Just Spray on Kwik-Clean & Wipe Off! ELIMINATES 'WHITE MOLD' Caused by Flux and Patina being left behind. Cleans off the flux too. Or spray on Kwik-Clean after applying patina to neutralize and clean up the left-over patina. No water is required for cleaning the window. Foil: The Kwik-Clean solution is a liquid, not a gel. So it goes under the foil (in the air pockets where patina can be hiding) and neutralizes the patina. This is the area where White Mold starts to form. Lead: The Kwik-Clean solution, when sprayed on the solder joint, easily rolls completely around the joint removing all the flux. After the patina is applied, Kwik-Clean goes into the little pockets left in the putty and neutralizes any patina hiding there. Comes in an easy to use spray bottle!