I am very sorry that you may have lost most most of your chicks. You can check for signs of life by putting the remaining eggs in a bowl of room temp water; they will wiggle if alive. You can candle them and see if any have pipped internally (broken the air cell membrane with their break.) Look at the threads on assisted hatching, if the chicks are alive and too big to hatch normally, you will need to help them, be careful not to break the membrane where the veins are, or the chick may bleed out.
Either sell the lonesome chick or buy him a companion chick or two. Keep them in a warm well-ventilated brooder (see threads about care of new-hatched chicks.) Show them how to eat and drink.
Open the dead eggs at the air cell end and post pix of them. If your humidity was too high this can cause chicks to be too big to hatch. The air cells will be too small and some of the chicks drown inside the egg if this is the case. This is why people here trace the air cells with pencil on Day 7, Day 14, and so on. Look for a chart of chicken egg development online; you will see that the air cell takes up about a third of the egg by Day 18.
Wash your incubator bottom and grid with 9 parts water, one part bleach, and a little dish soap. Rinse it, let it dry in the sun for the next use.
What kind of incubator are you using? What temperature did you keep the eggs at? What humidity?
How old were the eggs when you got them? Did you take out the red ventilator plugs in the lid on Day 18 so your chicks could get enough air?
If you are using a still air Little Giant 9300, the factory pre-sets the temp at 99.5 degrees. You need to either install a fan or set the temperature to 102 degrees, or the eggs will develop too slowly, being too cool to develop normally. Your instruction booklet will tell you how to change the incubation temp. If you bought the thing used and do not have an instruction booklet, look at the three red buttons on the lid.
This is what my booklet says: "To adjust the setting temperature, press and hold the SET button for three seconds (the setting temperature will begin to flash on and off.) Release the SET button and use the UP or DOWN buttons to adjust the setting temperature as needed. Press and hold the SET button for three seconds to capture the setting temperature and return to the current temperature. If no adjustment is made in ten seconds, the current temperature will display automatically." Don't let your eggs get too hot; 103 degrees is too hot.
There are so many things you can do to wipe out your eggs with this type of incubator, and your manual does not mention most of them. It is best to do test runs on cheap fertile eggs for a while until you are confident the machine is working properly and you know how to deal with its issues. The manual says my incubator's humidity sensor runs best between 60% and 80% humidity. It does NOT tell me that this range is far too high for the first 17 days of incubation and will result in chicks drowning in shell and the need for assisted hatching, but that is what BYCers here have found.
