Dark was saying that it would go in to the machine as dog food then be ground up and come out as roach food, not that he had a roach mix already. Dog food can be OK as a staple to sustain them but what most people do is then feed them a healthy gut load prior to feeding them off. Dog food isn't ideal but it is cheap, easy to find, and works. Put good in, Get good out.
How long have you been keeping them like that Jarich? Too much calcium is deadly to Dubia and since you can simply put the calcium on the outside prior to feeding it seems silly to put extra in their diet. Once or twice a year cleaning is just asking for trouble. A year without cleaning at this point would fill up half of the tub with frass for me. I don't know how that would work. You would also think that a dry food mix on the humid substrate would be a major mold hazard.