my cat sheds a lot! i brush him, but within a few hours the fur goes everywhere if i pet him. i'm having a difficult time keeping my bed fur free. i switched to innova dry food b/c it's supposed to help with the coat. i had him on iams and have been putting less and less iams in the with the innova. now, he's mostly on innova. how often should i brush him and can i brush him too much? how many minutes should i brush him? i use a brush with curved metal bristles and i get a lot of the undercoat each time i brush. it's hard to get his stomach area b/c he rolls around too much. he loves getting brushed, and will roll onto his back, but he runs away when i start brushing his stomach. he's medium hair.