redish poo

Is your roo acting sick and how often has he done it? Chickens sometimes shed intestinal lining, which is normal, this chart has examples http://chat.allotment.org/index.php?topic=17568.0
A full molt usually takes a good three plus months, most won't drop all their feathers at once, but kind of in sections (some chickens, especially frizzles, do drop a lot at once though, take a look at the BYC Worst Molting Pictures Contest). http://www.thepoultrysite.com/articles/217/moulting-a-natural-process

 

If he's acting normal otherwise, its probably just shed intestinal lining. However, if he has other symptoms, like lethargy, it could be Coccidiosis.

Molting can take less than a month, or as much as four months. Most of my birds molt in around 2 months, but some take longer.

 

How old is he? Does he act fine otherwise? Its probably just shed intestinal lining; this happens to chickens ever so often. But if it is happening frequently, and/or he is lethargic, not interested in feed or water, or showing other symptoms, then its possible that he has Coccidiosis. In that case, I'd get some Corid and begin treating him.

As for molting, the time spent molting varies depending on the bird. I've had the molting times from birds of the same age and breed vary from 1 1/2 months, to at least 4 months.