I’m planning to harvest honey for the first time tomorrow. Several of the flow honey frames are mostly capped. I have a refractometer, but I don’t know how or when I should measure the moisture content. If I crack open one of the frames, let the honey flow into the tube and then find out that moisture is too high, aren’t I then committed? How do other flow hivers measure moisture content? Thanks,
Joe
You are a bit yes. You only need a small drop of honey to measure moisture, and if it is capped, you can assume the moisture content is low enough for harvesting. The issue comes when it is NOT capped. In that case, I would just dip a cocktail stick into an uncapped cell and let the honey drip onto the measuring surface of the refractometer. Don’t forget to calibrate it first (I use extra virgin olive oil, which has a moisture content of ~27.2%).
Hope that helps! 
Thanks for your advice Dawn. I just finished harvesting two flow frames. Both were at 16% water, so I’m really happy with that.
And at the risk of getting a little too geeky, it was a lot of fun seeing the honey flow into the jars. My adult son and I had a great time doing that!
Joe