Our Checkered Giant is getting near the end, at 12 years and has pretty much stopped eating hay too. Since she's never had a sludge problem and doesn't really have that much time left, I got her some alfalfa and she's eating it like she used to do with Timothy. In the past with the younger buns that were healthy I reduced or removed the pellets till they started eating hay like they should have all along. Our old girl has gotten really thin and doesn't get around too well so I give her as much pellet as she wants too. She's had a good life since we rescued her and she's just been an amazing, loving bunny that this is very hard on me.