If you will use the search function at the top of the page, you will see this is a subject that has been beat to death. It really is just up to each individual person. Personally I DO NOT reccommend washing any egg, either for consumption or for hatching. Eggs are porous and they absorb anything that touches them. So I do not want to wash an egg with poop on it, knowing that that egg is going to absorb poopy water. I do however have a little trick you can try. I keep a coffee can full of clean play sand in the hatching house and I use that sand to gently scrub the filth off, ONLY if it COVERED in poop. Other than that, it stays the way I found it. It works better than sand paper because it is not as rough on them.