Are overdue eggs supposed to sink when water candled?

[Marliss51]

I had this experience last night. This is my 2nd experience with the Little Giant 10200 incubator. So far 15 chicks had hatched from 23 viable eggs. Yesterday was day 22 or 23 and hatching had died down. So I floated the 7 remaining eggs. 2 floated, 5 sank. I put all back in the bator just to be sure since there was one piping in there already that needed more time.

Last night I candled ALL the eggs. The 2 floaters had no movement and they did not peep when tapped. BUT, one of the sinkers was quite noisy and active in his shell. So once again, I put them all back in the bator while I feverishly searched for clues on what to do. After all, I thought, doesn't an egg need an air pocket to float....and is the little guy going to suffocate?

Fortunately, he pipped later that night. This morning the hole is much bigger and 2 more eggs are opening. Any thoughts?

P.S. I think my eggs are overdue because the temperature was too low. I'm thinking the Little Giant thermometer was right after all, not the other 2 I used for comparison.

 

[AmyLynn2374]

I had this experience last night. This is my 2nd experience with the Little Giant 10200 incubator. So far 15 chicks had hatched from 23 viable eggs. Yesterday was day 22 or 23 and hatching had died down. So I floated the 7 remaining eggs. 2 floated, 5 sank. I put all back in the bator just to be sure since there was one piping in there already that needed more time.

Last night I candled ALL the eggs. The 2 floaters had no movement and they did not peep when tapped. BUT, one of the sinkers was quite noisy and active in his shell. So once again, I put them all back in the bator while I feverishly searched for clues on what to do. After all, I thought, doesn't an egg need an air pocket to float....and is the little guy going to suffocate?

Fortunately, he pipped later that night. This morning the hole is much bigger and 2 more eggs are opening. Any thoughts?

P.S. I think my eggs are overdue because the temperature was too low. I'm thinking the Little Giant thermometer was right after all, not the other 2 I used for comparison.

I hate the float test because it's unreliable. Did you candle before you floated them to make sure there wasn't any internal pips?

Here's my thoughts: (and I could be wrong) If it was noisy and active it had already internally pipped. Which means it was breathing the air in the air cell and that space was being filled with carbon dioxide instead of air. Carbon dioxide is heavier than oxygen. It probably doesn't allow the egg to float.

I don't recommend float testing, but if you float test, you should always candle and make sure that the chick is not internally pipped, or that there might be a crack in the egg that isn't discernable by the naked eye that could let water in and drown the unhatched chick.

The carbon dioxide build up is what urges the chick's body to progress to an external pip.

That's real surprising if the LG's temp were accurate and the other two weren't. Digital LGs are known for their temps to be lower than the readings. Are both of your other thermometers digital?

 

[AmyLynn2374]

And:

 

[Blooie]

As usual, Amy is spot on. I don't water candle overdue eggs unless I can't be sure from candling with the light what it going on inside that shell, and even then I make sure to light candle carefully to make absolutely sure there are no missed cracks in the shells first. My eye is still less discerning than Amy's when it comes to spotting less obvious internal pips, but I'm learning.

The sink-or-float test is looking for freshness with eggs you plan to eat. There is always some confusion between the terms "water candling" and "float testing"......with water candling you put one egg the warm water at a time and watch it for a few minutes. If there is a moving, active embryo it will usually wiggle a little bit in the water. But, as with most things chickens, there are no guarantees. I've done it with three hatches, (one incubator and was fortunate that it was right on the money both times. But I had one that, even with light candling and then water candling, I was still fooled - which meant I may have tossed a viable egg or two, and that's not acceptable. I think I'm learning to be more patient and let time tell me if it's time to toss or to keep going.

Welcome to BYC, by the way! Good people here!

 

[trifecta]

What type of flashlight are you using to candle? Up until last night I had been using a superbright LED bc I have brown and pigmented eggs in the bator. I had always thought I just couldnt see much due to egg color, but I found a post on here discussing using a flashlight with yellowish light rather than led bluish light.

tried it last night and was amazed with the difference. The maglight I used was visibly not as bright as the LED but wow I could see everything, including internal pips. Anyway, have you tried candling with a different flashlight?

 

[Marliss51]

Thank you all very much. Those were all some great suggestions. I never thought of CO2 being heavier than air. And you guys are definitely right about the water candling test being unreliable. I may have thrown out 2 viable eggs during the last hatch. Oh well, live and learn. At least I didn't throw out these.

As for the LG thermometer. It was reading 1.5-2 degrees LOWER than the other 2 house thermometers I checked it against.
I marked the "true" 99.5 on the LG and went with that. I don't have a digital thermometer. Is there one that you guys recommend?

It was daylight when I did the water test, so NO, I didn't candle first. When I checked them last night, I didn't see movement in any except the one that was peeping. I tried to look for internal pips, if they were there, I didn't recognize them. I will try a different flashlight next time. The green egg was especially hard to see anything, but I was able to see the little peeper moving in there. My other eggs are all brown or light brown.

One more question: When do you start counting? I put my eggs in the incubator at 5 p.m. on a Sunday. Is day 21 going to be on a Sunday or on Monday?

 

[Blooie]

It'll be on Monday, @Marliss51 since the end of Day 1 isn't until 24 hours has passed.

Edited to add: If you find the 100000000% accurate way to find exact temperatures, let me know first please!


I have sitting here 4 wireless digital thermometers, 1 probe digital thermometer, one highly recommended aquarium thermometer, and one bulb thermometer which came with my incubator. As you can see, the readings vary greatly even though the transmitters (in the case of the wireless ones) and all of the others are sitting side by side in the same spot. <sigh> The aquarium thermometer reads 73 degrees and the other bulb thermometer read about 74. The only thing I truly trust in that entire ensemble is the hygrometer, and that's only because I did the 10 hour salt test on it and adjusted it as it still sat in the plastic bag along with the salt sludge container, no easy feat, I must say! None of these slight variations make a hill of beans worth of difference if you are deciding whether to wear a coat outside or not, but make a heck of a difference over 21 days of incubating eggs, especially if you paid a fortune for rare eggs!

 

[Marliss51]

I think I got that right. When my other 2 thermometers read 99.5, the LG reads 96.5-97.0 Hard to read numbers that small.

 

[AmyLynn2374]

I think I got that right. When my other 2 thermometers read 99.5, the LG reads 96.5-97.0 Hard to read numbers that small.

So if your incubator thermometer was lower than the independent thermometers and you adjusted up according to the independant thermometers, it was still cool..... did you add a fan to the incubator, or is it still air? If it's still air, it should be 101-102F with the temps taken near the tops of the eggs, (which is where the sensor for those usually fall.)

You start counting after the eggs have had 24 hours of incubation. So if you set on a Sunday, you should expect hatch (providing temps were accurate) to be on Sunday 3 weeks later.

If you are using glass thermometers that go down to 32F you can check them using the ice water method. You take a glass of ice and put cold water in it. Give it a couple minutes to come to temp and stick the thermometer in it. It should settle at 32 degrees. If you have an accurate thermometer you can check it against all others. Many people like the Brinsea spot check thermometer. You can get it online around $20 I think. My digitals cost me $5 from Kinney drugs...lol

Greens are harder to see into. An internal pip when you candle, you are looking for a shadow, using triangular in shape, moving around up in the air cell. If you hear peeping inside the unpipped egg, that's a sign it's pipped.

 

[Marliss51]

My incubator is forced air with a fan.