Hi Bunny Bugs. I have lived this problem with my bunny since October. I don’t know how old your fellow is, but everyone will tell you to put him on an all hay diet. I wouldn’t do this all of a sudden. I never got my girl totally off pellets. I offered her lots of hay and different kinds, too. I actually fed her a lot of those dried Timothy w/ carrot treats as well as the barley ones. Plenty of hay and just small amounts of pellets spread throughout the day in hopes she would eat hay in between. I also found I could give her cilantro, but other people have reported their bunny not tolerating that. Most I would offer is dry stuff. I even dried Kale in the oven and cilantro hanging in the house drying. I feed her dry apples. She seems so thin that I didn’t want her to get to skin and bones, so I don’t worry about the calories. But hay hay hay. Gracie is very accustomed to being washed. I have done both simply holding her under the faucet of the wash tub, on her back, with a paper towel and watered down mild pet shampoo, then rinse the bum well. I have also stuck her bottom end in a bucket of water to soften and remove the yuck. I always use watered down shampoo though and rinse well. Also, I’ve found that if it dries it can be combed out. But it’s not a perfect fix that way. Some people just give their rabbits an all hay diet for a day or two and it takes care of things. You just don’t want the bun to starve himself.