Arches Aquarelle, soaked in a solution of 2% ammonium chloride and distilled water, with 12% AgNO3 brushed on after drying (AgNO3 solution also contains 6% citric acid). Paper is dried, then contact-printed, everything looks okay, washed with tap water (5-10mins), fixed in 5% sodium thiosulfate (5mins), washed (5mins), hypo-clear (5mins), washed (~10mins). Somewhere in the wash, part of the print will discolour to blue. I figure it might have something to do with my tap water? Perhaps the chlorine?? Any ideas??