Ok. Please try and find a way to measure the humidity inside the box. Always provide nesting pairs with a bowl to bathe in so they can self regulate to some extent.
You should be candling the eggs often; I candle mind at least once a day. You should teach your pair to get used to this. Mark each egg as it is laid and keep a detailed record of when each is laid and when the hen starts to sit. A few days before the egg is scheduled to hatch you should begin to candle every day if you aren't already. Watch for the baby to pip. Monitor the hatch as it progresses. If there is not enough humidity the membrane will dry out, glue the baby in place inside the egg, trapping, and killing him. If the baby isn't able to progress, you will need to step in and assist. However assisting even an hour too soon can kill the baby, as will waiting too long. Please do lots of research on the hatching process and the method of assist hatching. There is a lot of work that goes into raising cockatiels. Some people have tons of luck and never run into an issue; the rest of us have to research like crazy and work very hard to take care of these little lives. I have an egg hatching today; if it needs help I'll try to get a video of the process for you, but I am by NO MEANS an expert so please search out the expert instructions that exist on the Internet.
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