I am hatching chicken eggs in a Little Giant Still air incubator at a constant 99.5˚ (I know its low).
Today is the expected hatch day (Day 21, 100% positive it is day 21). I decided to candle my eggs and I was surprised. All of the chicks (5) seem tiny! There is a yellow see-through section of the egg at the bottom (small end) of the egg. The chick inside is moving, in fact, 2 out of the 5 were rocking the eggs before hand. Sadly they all seem very very tiny and I'm worried. Here is a diagram of what I mean.
Here is the candeing, notice egg is small end down and large end up in the image. Also the air sack is not visible (although it is pretty big) because the light isn't aimed at it.
The chicks all show signs of life, rocking back in fourth, visible movement inside shell during candling. Will any be able to hatch? Please help and give me advice on what can be done/ what went wrong. Tomorrow will be day 22 btw. Thank you so much!