Advertisement Well, I finally got my B. Dubia colony set up and it seems to be working beautifully. In another few months I should have a self-sustainable roach community on my hands! Now here's my question for all you other more experienced colony keepers: How often do you have to clean up their waste? I have noticed that in a few short days they have already left droppings all over the floor of the tub. This is a very small colony I am talking about (around fifty roaches). So how often would YOU clean their cage?