I know fertility is rarely 100%, and there is no way of testing fertility before setting eggs. So what does everyone do with the inevitable (though hopefully only occasional) clear eggs at the first candling? Just throw them away? Cook them up and feed them back to the chickens? If it were early enough (say day 3-4) could you blow the clear eggs out to save the egg shells, or will cooking at 100 for a few days be enough to turn them into stink-bombs not worth blowing out?
All of the above are OK. A truly clear egg can be blown out no problem. In fact you can blow them out and scramble them up for the chickens. In the old days hatcheries pulled clears and sold them to bakeries and such. Ewww. I sometimes set mine out in the back field for the ravens which in turn keep away the hawks and eagles.
My 7 year old son loves flinging them, and the chickens find the juicy remnants and eat them. But your ideas are much better.
I crack each one in a bowl, checking for progress. I save the egg shells (as I do all my cooking eggs) and microwave the cleaned out shells and mash them into powder for the garden. Then I dump them down the sink... or toilet if it's further along in the process. The only shells I don't save are the ones the chicks come out of in the incu.
I put all the clears and even early quitters (I candle often) in a sauce pan, crunch them up shells and all and feed them back to the flock. Protein for everyone. Some folks may find it disgusting to cook the very early quitter embryos and feed them back to the chickens, but consider some of the things you've seen your flock eating.
