I have a colonoscopy, my surgery was in September so I am still in the learning process. My home care nurse determined a convex wafer would be best for me because my stoma is retracted and we tried a couple different ones. I still was experiencing leaks almost daily but at a visit to the ER due to bloody stool leaking, the on call doctor used Tincture of Benzoin to "glue" everything to my skin. My husband is the one who changes my appliance because I can't see to do it, due to the placement on my body. He first uses a crusting technique to protect my skin when it is reddened, and uses the tincture over that when dry. He also uses it on top of the seal before applying the wafer and bag. We don't use paste. This has been a world of difference for us. The tincture is most widely used before applying Steri-strips to a wound to help them adhere to the skin. Removing the residue from my skin is somewhat more laborious than it was before we started using the tincture, but it's worth it. We have gone from daily changes due to leaks, to being able to go 5 or 6 days between changes.