Fermenting is VERY flexible... I would start with a pint of dry feed in a quart jar add enough water to cover the feed and let it work at room temperature. If the chicks haven't hatched by the time it is ready, take a quarter of it to start another jar at room temperature and put the first jar in the refrigerator. When the chicks are hatched, dried off, and ready to start eating, spoon out enough from the first jar to keep feed available all the time. It will probably take days to finish the first jar unless they waste a lot of it. That is okay.
As the second jar starts to work, slow it down some by putting it in a cooler place or slow it down a lot by putting it in the refrigerator. When the first jar has a half a cup or so left, add more feed and more water and start feeding from the second jar. Or refill it from the second jar and put more feed and water in the second jar.
If they start eating it about as fast as the renewed batch ferments, start making the batches a little bigger.
It is really hard to say how much food per chick per day because it will start with very, very little and increase pretty fast.