Only 1 chick hatched three incubations in a row

[ChickenCanoe]

My incubator is a Amazon sold Life Basis, which appears to be just a Janoel 10 with an automatic turner.

My first hatch was ebay quail and I got a near 75% hatch of the fertile eggs. Not bad for my first ever incubation. I used the dry incubation method.

My next 3 attempts at chicken hatches have been disasters. In each group, only 1 chick hatched.

The chicken eggs come from my flock, a combination of OEGBs, domestic RJF, white leghorns, and Wyandottes. A large range of different hens and roosters so lots of varied genetics.

I used the dry incubation method on the first chicken attempt, then standard temperature and humidity parameters for the next two hatches. I have cleaned the incubator well between attempts with alcohol, soap, and diluted bleach water.

Each batch consisted of 10 eggs. On all of the clutches, all of the eggs were alive developing at the end of week one, half had died by the end of week two, and the rest die between weeks 2 and 3, always except 1 chick.

I have tested my thermometer/hydrometer and confirmed its accuracy. I don’t know what to suspect except a ventilation problem, a problem with how the eggs are turning, or perhaps contamination with a chemical. First time I cleaned the incubator I used some sort of wet wipe, not thinking about what chemicals might be in it.

There are only 3 small vent holes in the bottom, only about half a centimeter across. They are on a thin lip that is barely lifted up off the desktop the incubator sits on. The unit’s fan sits on the top of the unit in the center and pulls upward.

Do you think I’m on the right path suspecting a ventilation issue?

You haven't looked at all the possible causes of failure.
I wouldn't start modifying a new incubator without eliminating other causes.
After all, it hatched quail just fine, why wouldn't it hatch chickens without modifications?
A fan should circulate the air inside the incubator not pull air in or push it out. That would be excessive ventilation.
With what you describe, the first place I would look is at your breeder nutrition.
What do you feed your birds?

 

[Florida Bullfrog]

I feed them 16% laying crumbles, occasionally Purina game bird chow, oyster shell, leftovers from my garden, and whatever they get free ranging. They free range my 40 acre blueberry farm from daylight to dark. I’m in north Florida, so we don’t have cool weather until right now in mid November. Abundant insects and browse.

One of my Florida Cracker game hens just had a nice hatch. She is my first hen in this flock to set. I also sent a couple of dozen eggs to the University of Florida for one of their agg programs to hatch. I’m awaiting to hear how those did.

I’m reasonably sure its a ventilation problem. I’ve spent a lot of time since my initial post studying incubators on Youtube and it seems like most have quadruple or more times ventilation holes and larger size than this incubator has. To the point that my incubator seems ridiculously sealed in comparison.

 

[Florida Bullfrog]

I figure the little quail eggs may have different air requirements both being a different species and significantly smaller in size.

 

[CindyinSD]

You said you did your first hatch dry and got a 75% hatch rate. Also you’re in super humid N FL. I would try the dry hatching again, or maybe I’m misunderstanding the question.

 

[Florida Bullfrog]

I drilled out the 4 small holes last night. 3/8” looked kind of big to me so I used the bit that was the next step down 5/16”. I also added 4 pairs of smaller holes around the rim of the plastic near the bottom. Overnight the incubator seems to hold temperature well. Biggest change I can see is that humidity is cycling out faster. I didn’t fill the water trays, just left the water droplets in from where I washed it.

Humidity in the house in AC runs around 50%-60%, but within the incubator it will dry out to almost nothing if the water isn’t kept in the trays. That was true before and after the drilling of the vent holes, its simply a faster process now. Humidity started at 90% last night around 8:30pm and by middnight the humidity was down to less than 25%.

As measured by some strands of cotton, the 4 air holes on top are pulling air in 2 holes and pushing air out the other 2 holes.

I’m going to put a batch of eggs on tonight. If they come out fine, I’ll know ventilation was my problem. If I have the same results, I’ll rule out ventilation.

 

[FortCluck]

I'd do the incubation dry until day 18. I'm in VA and it's humid all the time so I'm keeping the water out until day 18 then I'll add some so I get 50-55% humidity. Once the chicks start external pipping the humidity will be higher.

 

[ChickenCanoe]

You won't know for sure the humidity is correct for your eggs and location unless you weigh eggs before and periodically during incubation.
Weight loss of any avian egg should be in the neighborhood of 13% during incubation regardless of species except perhaps megapodes .
https://poultrykeeper.com/incubating-and-hatching-eggs/weight-loss-method-forl-incubation/
A loss of 55 points of RH in 4 hours would concern me. You can always cover some of the holes you created with some tape.
I probably wouldn't have started modifying a new incubator unless I was sure of the problem but if I was going to drill holes, I'd start with one, not four.

Did your lone chick that hatched, hatch early, late or on time?

 

[Florida Bullfrog]

On batch 1, the lone chick hatched on time. On batch 2, the lone chick hatched on day 19. On batch 3, the lone chick hatched on time. Chicks 1 and 3 were leghorn crosses. Chick 2 was a RJF or derivative bantam (correction, chick 3 was a OEGB, not a leghorn mix).

 

[FortCluck]

I think you're doing fine and adding ventilation will help. Cover maybe 1 or 2 of the holes with tape then check the humidity.

You said you checked the temp and everything so you're probably good!

It could just be the incubator itself causing issues like the overall design of it. Could also be the breeding stock. Maybe try eggs from someone local to see if their eggs have the same issue.

I know my eggs are completely different than the local eggs that I picked up, the local eggs I lost three already out of the five... I've lost zero of my own eggs.

 

[Skippersnh]

i suspect your humidity during incubation is too high because your dry hatch worked good the only thing that has changed since your 75% hatch rate is you added humidity and now your having problems