I made a print today and used my usual pt. toner, by Bostick and Sullivan, basically 1/2 L, citric acid, and 7 drops #3 pt. solution. I also used a heavier paper, Arches Watercolor, 140 lb. I have been using Cranes kid finish white which is considerably lighter than the Arches Watercolor. I toned for 16 minutes and not much happened. My last print on Cranes kid finish was well toned after 7 minutes. Does it take more time to tone a print on heavier paper? Does anyone have any numbers on how long it might take to tone a heavier paper or do I need to change toner concentration or something else? Thanks for any help.