Originally Posted by saccw
From your measurements, your OG was 1.064. With that recipe, you'd have to hit 80% efficiency to hit that OG, which may be in your normal range. If you're at 1.030 now, you're only at 4.44% ABV, without accounting for the lactose (my copy of beersmith can't account for lactose affecting the gravity but being unfermentable). If it has been stable for 3 days then rousing the yeast may help as will kicking up the temperature.
I don't use dry yeast, but I often read that making a starter from dry yeast will really tire them out by depleting their nutrient reserves.
I wasn't aware of that, so that may have been what I did wrong. I'll start pitching my dry base starters with some nutrient and see if that helps.
As for the lactose, this is what I was told in another forum: "lactose adds 42 points per gallon per pound. So, if you added one pound to 5.5 gallons, your FG will be raised by 7.6 points"
So my OG would have been closer to 1.072 with the added lactose, and my final gravity should have been 1.023or 1.024 (it was 1.018 the first time I made this same beer, but with 1/4lb less lactose) so given those numbers and what I hit last time, I should have been down to around 1.020 FG (I believe). So I'm not as far off as I originally though, but still a little lower than what I was expecting.
I'll try raising the temp up a few degrees to try and kick start them and see if I can't get them to finish up a few more points.
Originally Posted by flars
Are you using a refractometer or hydrometer for your SG readings? A refractometer will not read accurately with alcohol present in the sample. Take a SG reading with a hydrometer, if you are not using one.
Hydrometer. I tested it in water as well, just to make sure it was accurate, and I was sitting right on 1.000.