I am new to incubating chicks. On Saturday only ONE out of TEN I put in the inc hatched. SOOOO disappointed. I have a borrowed Brinsea Octagon 10 which I put in 10 eggs from my flock of 1 light sussex cockerel,1 Pekin bantam cockerel and 1 Buff Orpington hen,3 hybrid brown ISA, 1 hybrid speckldy. It's all a bit of mix as I am still new to keeping chickens.
After 10 days, I candled them, 2 were infertile and 1 which I thought was no good had a heartbeat when I opened it.
I candled them again at 14 days and they seemed fine all with heartbeat. The day before they due to hatch(on Sat), 1 pipped but still couldn't get out by Sunday lunchtime so I helped it with warm wet tissue soften the shell. It finally got out and now is doing well.However all the remaining ones have failed to hatch, I opened them today and most were smelly and had died before taking shape. Only had 1 complete chick inside obviously failed to get out. I noticed the membrane was really thick so I suppose it had difficulty. I would like to have another try with the same incubator. How can I avoid making the same mistakes and get better results? P.S. I washed the eggs with warm water very gently before wiping them dry and setting them, always washed my hand before candling them, filled both water reservoir on day 18 when stopped auto turner. Not sure what I did wrong?

