Originally Posted by Evan!
Temperature matters. Most Hydrometers are calibrated at 60f. What temp was the water you tested?
Tested at 65 degrees, BUT that is the temp I always measure at, so it should be consistantly incorrect.
Probably get OG at 75 degrees.
I doubt the water quality/ mineral amount has changed.
I keep an extra hydro for emergencies (broke 4 iin the last 10 months), will check the two against eachother.