I candled their first clutch yesterday, and it looked to me like big yellow yolks and air bubbles...but I have never done this before so I am not sure I know what I am looking at (only have photos posted here to go by), but I certainly did not see anything that looked like red veins. Those eggs - along with one laid by the Society - are still under the Society. I thought I would candle them all again tomorrow - that would make the eggs between 8-10 days old, and the lone Society egg would be 6 days old. I should be able to tell for sure then, right?
Thanks for all the help!
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Hi again everyone,
I have a few questions about our Green Singers, but first a little background:
They spent several days earlier in December flying all over the cage with bits of nesting material in their beaks. They mated that I saw several times, and built the saddest looking nest imaginable! I helped them out by adding to it, and for my first attempt, I was pretty pleased with the nest I built for them. They proceeded to lay three eggs, one a day for three days. The nest is in the top left corner of the cage and is very sheltered with silk greenery, making it very private for them.
The hen incubated well for one day, then more or less stopped. We waited one day to see if she would return to the nest, but she did not sit tight so we removed the eggs and placed them under a Society hen who had laid one egg the day before. For the moment, we are leaving the Society hen in the large indoor community cage with three other Societies, and Spice, and an Indian Silverbill. There is almost always at least one finch incubating...sometimes up to all six! It was suggested to me in a kind response to another post I made here that I remove the entire nestbox and the suspected parents before the eggs hatch for fear that six finches on babies might lead to flat babies! And I will do so...
My questions are really about the Green Singers. Since I removed the eggs and replaced them with fake eggs, the Singers have proceeded to totally deconstruct the nest they and I built. I have left the three fakes eggs in there. The Singers are again flying all over the cage with bits of nesting material in their mouths. They have been doing this for three days, but there is not a single bit of nesting material IN the nest! It's like they are just playing with the bits of nesting material, or do not know what to do with it! I have seen the male feeding the female again, and I have seen them mating again. But they sure do not have nest-building or incubating down!
Should I remove the fake eggs in their nest? Should I make another nest for them? Should I decrease the amount of full spectrum light they are getting every day and try to get them on a more "natural" (wintertime) schedule and try again in the springtime? Should I just stop worrying and leave them alone?

I have to check my calendar and count days to remember when exactly I placed the Singer eggs under the Society, and I think I will try candling this time (I did not do it with the canaries I have - two pair - who just laid six eggs and only two of the six eggs hatched) - it might be today or tomorrow that I can do so.
We are really just perplexed here by the Singers' behavior, and feeling a little frustrated because so many on the forum with Singers seem to have no problems with them breeding very successfully. ANY ideas, thoughts, advice, suggestions are welcomed and appreciated! Thanks in advance!