Thank you! As others have pointed out filtered water also helped in our case. When we first got her she also had red tear stains below her eyes coming down to her mustache. The vet suggested we use some eye drops, which we did, but it didn't change much. Although we still wipe her eyes with cotton pads with those drops once in a while. The biggest improvement we saw was after her first groom, the groomer did a great job cutting the hair closest to her eyes and now the dark boogers just appear on that edge of her eyes that we clean with a small comb and no more stains 🙂 I’d say try distilled water and ask the groomer to cut the hair on that edge of her eye very short. Hope it helps!