its not really that simple as asa has neglected to mention the whole bit between the eggs hatching and the maggots being ready to pupate. while i have never raised maggots with dog food, i have raised them on raw chicken liver. the eggs are layed, and then in a few days you will see a mass of little maggots eating away. they grow surprisngly quickly, a few days after you first see them they will probably be big. i dont really know the properties of dog food, but when i use chicken liver it dries out very quickly. the maggots only eat the "inside" of it, the parts that are still moist, and leave the dry outer layer. i imagine dog food stays moist longer but you will probably know that more than me. when they have eaten and grown enough, they will look for dry places to pupate, and this is when you will see them crawl away from the food/up the container sides. there is not really any need to clean anything as they will eat the decomposing stuff. once you see them crawling away from the food, remove any remaining food. if you want you can check the food, as sometimes they go ahead and pupate right there amongst it without bothering to crawl away from it, though i guess this is because my chicekn liver is dry enough at this point. the sawdust is optional, they dont need it to pupate. however if the container theyre in is not very well ventilated (you said the air holes were tiny), moisture may build up allowing the maggots to climb the container sides with ease, at which point they can cause trouble by escaping out of holes and such. so if you notice this happening, some sawdust would be good, or even just some tissue will do the trick (to absorb excess moisture). once they pupate, like asa says, you can fridge them and take some out every once in a while etc. be prepared for the smell, i hear it is pretty bad! (decomposing chicken liver certainly is
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