Can too vigorous an initial fermentation cause a stuck fermentation?

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BBFCreatureFM

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I think I may have a stuck fermentation?

I made 8 gallons of all-grain Belgian Blonde sticking fairly close to Revvy's recipe (scaled up). I hit my pre-boil numbers, but I boiled for too long and way overshot my OG, which was 1.081. Rather than dilute it with water, I just split the batch and pitched a 2L starter made with two vials of Abbey Ale (White Labs WLP530). I've read that this yeast is tolerant of higher alcohol (up to 15%), so I figured I was okay even though my wort was sweeter than planned.

The fermentation went gangbusters and needed blow-off tubes for three days. I fermented a bit above the optimal temperature, maybe 72 degrees ambient temp. But now (two weeks later), my gravity has only dropped to 1.045. I added apricot puree to one of the two carboys, so that one has new sugars and new airlock activity. I also slightly agitated both carboys. I'm going to wait a few days and check the gravity on the non-apricot carboy to see if it has in fact stopped at 1.045.

Is it possible that I overstressed the yeast by having too active an initial fermentation? Or maybe I overpitched? Can either of these things cause a stuck fermentation? I expected a bigger drop after two weeks. It is going to be a sweet blonde, if that much residual sugars remain. Is there anything that I can do, if in fact it's stuck at 1.045 when I test in a few days?

Most likely, I just need to sit on it and not worry.
 
I have never heard of those things causing a stuck fermentation, but that doesn't mean it's not a possibility.
A few questions:
Was the starter on a stir plate?
How did you aerate?
What it the temperature now?
 
The starter was not on a stir plate, but had been agitated manually for over 24 hours when pitched, and had its own krausen going when I pitched it. I aerated manually as well, just shaking the crap out of the carboys. Temp is still around 72 (ambient). Maybe I should try and warm it up?
 
Hmmm... That's the same way I do a starter, and the same way I aerate. 72 should be plenty warm.

I'm just about out of ideas. Are you using a refractometer and not compensating for alcohol? If that's the case then it is done and the gravity is much lower than it seems.

Here are the top ten reasons why your final gravity may be stuck:
http://woodlandbrew.blogspot.com/2012/11/top-ten-reasons-why-your-final-gravity.html
 
Is it possible your hydrometer is out of calibration? That would explain both the high OG and the high SG, especially if the little peice of paper in the glass window slipped. Toss it into a bucket of tap water and see what you get.
 
I was using a refractometer and not compensating for the alcohol. It's actually down to 1.019, after compensating. I just bought the refractometer and I will be perfectly honest, I did not even know that there would be math involved in post-fermentation gravity readings. Much ado about nothing, apparently. Thanks for all your help.
 
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