Carb bubbles in hydrometer tube

I've got a Summer Ale fermenting with Safale 33 in a glass carboy now. Its been sitting in there for 10 days. Today I took a hydrometer reading. Double bad news. FG hasn't continued to drop past 1.020 (it was at 1.020 on Thursday) and I have carbonation bubbles in the tube?

Why would I have carb bubbles?

Should I keep it fermenting?

OG was 1.054. Temperature spike may have caused this. Been around 76.

CO2 will bouy up your hydrometer giving you a higher reading than actual. you have these bubbles because the CO2 is in solution and your test jar and hydrometer have surface scratches and is causing the CO2 to come out of solution. Easy solution, spin your hydrometer like a top in the jar, this will force the gas bubbles off of the hydrometer. Take your reading one it stops moving.
Keep fermenting, it should continue to drop slowly over time.

If you don't understand, the reason you have carb bubbles is because the two by products of fermentation are alcohol and carbon dioxide. So there is CO2 present the minute the yeasties eat sugar they produce both.

so i tried again to get a accurate hydrometer reading. still had bubbles so i tried to spinning technique. no change. i am going to let it air out to see if it runs flat after a while.

i put a thermostrip on the carboy to see where the temp was at and it did indicate. does that mean the temp of my beer is above the high of 78 on the strip? that could explain the stuck fermentation right?

another question about this same beer

its now showing lots of activity in the airlock. bubbling at least every minute now. which is great, i think, because it means it will continue to drop below 1.020.

when i looked at it (glass carboy) there was a layer of white bubbles on top of the beer. not as dense as krausen but enough of a layer to be noticed. is that a fermentation by product or is my beer doing something else?

also it is not as golden yellow as it was a week ago. not sure if thats related just including the detail to get a proper diagnosis.

Most likely the bubbles you are seeing now are just CO2 bubbles coming out of suspension. Is it possible that the temp changed a bit? Perhaps the barometric pressure changed? I don't think its fermenting any more. It's probably finished @ 1.020.

should i bottle soon if the FG is still at 1.020?

The final gravity depends a lot on the strain of yeast and the recipe.
S-33 has average attenuation of 75%, which would indicate a FG around 1.014.
But if your recipe has a lot of crystal malt, or if you mashed a higher temp (say 158F), then your wort might be less fermentable than average.
Also, the brand and age of malt extract will have an effect on attenuation.

You say the temp was around 78F, which is at the top end of the manufacturer suggested range of 59-79.
This is OK for yeast performance and small fluctuations wont hurt, but most brewers shoot for somewhat lower temp to get a better flavor.
Try covering the carboy with a wet tshirt or use a water bath with ice to lower temps a little.

If the gravity has stayed the same for this long, the beer is done.
Bottle and enjoy!

When I take a sample for a hydrometer reading, I put it in a small glass. Then I will vigorously pour the sample back and forth between 2 glasses. This will knock out all the gas, then I put it in the tube for the reading.

thanks for the help guys.

i'm going to take hydrometer readings this morning.

If you have a wine saver device (rubber stoppers and pump) I pour my samples into a clean beer bottle, attach a stopper and begin pumping. You'll see the CO2 bubbles coming out of the beer sample. With a little more shaking and pumping, the sample should give a more accurate hydrometer read.

I tap the side of the sampler tube a few times to dislodge any bubbles....then I spin my hyrdometer. And usually just leave it alone for a few minutes after. I've never had a problem, really.