Hydrometer help

[ChickenCrazy01]

I calibrated my digital(Acc-Rite) Wednesday before I set my incubator up. My hydrometer was reading 68% so I have been adding 7% to my humidity. I bought a Flukers hydrometer yesterday at the pet store and calibrated it yesterday and it was reading 78% so I have been subtracting 2% off the reading of it. I have both in the incubator since last night and I am getting the same exact reading 35% now when I don't add or take anything away. If I add to my digital or subtract from my Flukers then I get completely different readings. Should I re-calibrate the hydrometers or go by the readings they are reading?

 

[shelleyd2008]

I would re-calibrate them. Mix salt and water in a dish, enough so the salt looks like wet sand. Place the dish and the hygrometer inside a plastic baggie and seal it up for at least 8 hours.

 

[ChickenCrazy01]

Thank you. I will re-calibrate them today. This is what I did to calibrate them the first time, is Kosher salt ok because that is what I used.