UPDATE- Duck Eggs Candling
On day 8 of incubation, you spend a bit of time candling the eggs to check for growth. Candling is just using a bright light (originally it was a candle) to check for the growth within an egg. If none is found, it's time to discard the egg so that it doesn't explode or pass any bacteria or germs on to the healthy ones. Out of our seven we've got in the incubator, we had to discard two this time and then we will candle again Sunday to check for growth.