The Poultry Health & Hatching Forum

Discuss all health, welfare, hatching and incubation issues

Humidity level incubator last three days


I am now on day 18, almost 19 of our first time hatching eggs. I have a borotto lumia 16 incubator with a humidity pump. I read online that I need to get the humidity level to 75% for the last three days, but I cannot get it over 60% without letting the water go beyond the two water reservoirs. (If have been slowly increasing humidity since last night at the end of day 17 because I realised I couldnít just put it from 53% to 75% in one go.

What humidity level is the minimum for good hatching? A little water at the bottom is okay as it doesnít touch the eggs but I donít want to push it more than I need.

Advice is most appreciated.

Saturday, March 27th, 2021

Hi Benrue,

What was the outcome of your hatch?

Am interested to read this as I am on day 21 of a first hatch using a Borotto Lumia 8. I didn't use the humidifier until day 19. I set it to maintain an RH of 65%. Overnight it flooded the bottom of the incubator but only on one side (the front / middle compartment below the grid); the water level was just about to touch some eggs.

I switched it off and quickly inserted a battery powered humidity sensor w an LCD display. This showed a humidity reading of 69%, 5% higher than the Sirio display. The Sirio was still pumping at 64% and would certainly have wet the eggs if it continued. I am now monitoring the humidity with this extra sensor and turning the Sirio on and off manually.

I'm guessing that the sensor of the Sirio could be defective and, if so, I suspect that this accounts for some of the accounts of flooding that I've read.

A second issue, apparently, was that the pump was working for only one of the two water reservoirs. It looks as if these are designed to overflow into the bottom of the incubator and to provide there, a larger surface area for evaporation (humidity being a function more of surface area than depth).

I swapped the valve connectors around and am now waiting for the overflow into the 2nd compartment in the bottom of the incubator. It looks as if in doing so the water meniscus rises above the top of the grid at the right hand (water reservoirs) end of the incubator, potentially coming in contact with eggs at that end of the incubator -- surprising, and a poor bit of design if so.

So far there's no sign of pipping in any of the eggs and I have to hope that my opening the incubator v briefly to slip in an extra sensor hasn't adversely affected things.

My impression was that the humidifier was, to some extent, an optional extra and whereas I did test run the incubator before using it I didn't do a wet run, so to speak, with the humidifier. My mistake.

The documentation for the Borroto products is not great with, if not Chinese-grade gibberish English, certainly 2nd rate translation. E.g.,:

"By pressing indifferently on one of the two keys"... "then press the keys on impulse".

Sunday, April 17th, 2022


Eggs hatched ok yesterday. After initial flooding and later one-sided functioning the Sirio humidifier seemed to settle down. It was able to maintain humidity without further overflow into the compartments under the grid. I now wonder if it's supposed to do this at all?

Somewhere I read of someone increasing humidity in steps rather than all at once. Comments welcome if anyone has any views on this / experience with the Sirio.

Tuesday, April 19th, 2022

I always run the the incubator dry for 18 days, take it off the Turner, add water, lock it down and don't open until whatever is going to hatch hatches, end of.
No opening, no interference, hatch rates usually around 90%.

Thursday, April 21st, 2022

After the hatch I spent some time with two hygrometers and digital and analogue thermometers and testing the accuracy of the readings and effect of adding water in different compartments.

My conclusions so far

Sirio is not REALLY needed in this climate

There's no reason I could see why one valve worked and one didn't but I did find a lot of flakes of something I couldn't ID in the tube, as if it had been partially blocked. I cleared by running several litres of water through the Sirio.

Filling the two wells with the red tops is fine to get a humidity level of 45% (manual says fill one; doesn't work for me). No humidifier needed, just water in these wells.

Just adding the Sirio to boost levels above 45% for lockdown was not reliable, I suspect because there simply wasn't enough surface area of water.

What did work was adding water to the two middle compartments (in addition to the two externally accessible ones) and setting the Sirio to 60%. At that setting the right humidity was achieved quickly and readily maintained by occasional action of the Sirio. (With only external wells filled and 65% it flooded and risked wetting eggs before reaching set RH)

I came across a reference online to someone saying "I overlooked the bit in the manual saying to add water to the internal compartments" however it was for a different Borotto and there is no such reference in my manual.

Am on next hatch now, with Sirio switched off. RH of 45% (100% hatch rate last time). Will use Sirio set to 60% for lockdown, with water in two middle compartments. Pretty sure this will avoid flooding problem, which does seem quite commonly reported, so there'll be no need to intervene. Might try a dry hatch next time and/or dispensing with Sirio.

Friday, April 22nd, 2022

You must have an account to comment here.

You must be registered with an email address to comment.

Click here to create an account. It only takes a few seconds.