Could be urates in with his poop. Not positive. I havent seen that before..but im sure Tom will be along to help u out .It's wet cause I just scooped it out the soak. He doesn't eat corn. I feed him Romaine lettuce once a week when I give him calcium and vitamins. He gets grass daily and he's too small for hay so I ground it up and sprinkle it on his food. Also eats mustard greens and millet grass. Occasionally he has hibiscus flowers and leaves, strawberry and mulberry leaves with a slice of cucumber for improved hydration.