Originally Posted by Bricks41
I tested my refractometer against my hydrometer last night and I found that none of the sites are completely accurate. I think the closest a site got to was +.005. Conversion stated it should be a FG of 1.013, but the hydro read a clear 1.008.
I'm still on the lookout for a reliable conversion.
In my experience, there is NO completely accurate conversion. What does work is that when the refractometer reading is the same over several days, you know it's done fermenting, and often it's "close enough" even if not totally accurate.
I still usually check FG with a hydrometer and skip the refractometer after fermentation begins.