I do checks every day in all my cages for poo. If its there i remove it and all the substrate around it. Usually just a big handfull. (Aspen Bedding)
After a month or so i do a complete cleaning of every tub with chlorhexidine and replace all the substrate. If you dont replace the substrate at least once a month you will get a nice stink building up in your house. At least mine does. I have 24 snakes and 4 breeding quads of african soft furred rats.