two brews stuck at ~1.035?

Hi

I've got two batches ( a stout and a porter) of extract with steeped grains that have stalled at ~1.035. One started at 1.058 and the other at 1.056. They have been fermenting for 5 and 2 weeks respectively. Both were started with s-05 and fermented around 70-72f.

I hadn't taken a gravity reading on the first one until 3 weeks in and noticed it was still high, at which point i added a packet of coopers and stirred it up. there was no change in gravity after a week.

At this point i contacted the internet brew shop i purchased the malt extract from who said i shouldn't have stirred the batch or added coopers(i should have added another s-04). He said he had not gotten any complaints about the extract and that i should try lowering the temp to 65-68 and perhaps the fermentation would restart. Due to a weather change the temps did drop to 66-68 but there was still no change in gravity.

At this point i figured i'd add some dextrose to see if that would kickstart the yeast. visible fermentation started within the hour but after a week the gravity was still 1.036.

These are my first brews made without a kit and i am hoping there may be something i can do to avoid two batches of sweet light beer. I will bottle and probably enjoy them regardless, but i'm a bit perplexed and hope to avoid this in future brews.

Thanks
Ryan

There is nothing wrong with giving your brew a stir if it seems stuck, so dont worry about that. Try to only add the same yeast you started with unless you are trying to make a70 different sort of flavor profile all together (some high gravity brews will have you do this). Try to look up with the best fermentation temps for your specific yeasts are but even at 70 to 72 most ale yeasts behave fairly well. I am hesitant to tell you to add dextrose as it seems like there is plenty of sugar left in there to ferment. Does the taste of the beer correspond with the sweetness you would expect from the gravity reading? Does it taste odd like you have a bacterial infection that could be halting fermentation?

First off, I would always test your hydrometer if you are having surprising reading. Just to make sure you are not getting false readings. Get distilled water as close to 60 degrees as possible and take a reading. It should be a 1.000 if your hydrometer is working.

Otherwise, I think you did what you should. Lowering the temp wont to anything, and as long as you didn't introduce oxygen when stirring.

SG of 1.035 from OG of 1.056-8, that is very high. If it kicked up a bit after adding more sugar it seems is if the yeast is active but done with the beer.

As was pointed out earlier, check you hydrometer. I have broken so many of them I have lost count and I keep two extra just for the next time. Nothing like getting a higher reading than your OG to make you realize the bottom is gone and all the tiny ball weights are missing.
I still don't know if I drank them from a sample or they went out in the trub. With the number of times it has happened I would bet on all of the above. No problems noted except I am bald.
Best of luck.

Cooper's was the wrong choice, as it is not very good at fermenting complex sugars and won't help a stuck fermentation.

The key for stirring a stuck ferment is to not splash the brew. All you are trying to do is rouse the yeast that has settled. When I've had to do this, I just hug the fermenter and swirl it until the yeast is re-suspended. I don't even open the lid.

Finally, de-gas the samples. Fill the tube about half way and shake it hard. Once the foam has settled, put the hydrometer in.

Thanks for the replies

The first thing i checked was my hydrometer, which was good.

Coopers was the only yeast the LHBS had.

I added dextrose to see if the yeast or the extract was the problem. The fact that it started fermenting once the dextrose added would lead me to believe the extract is bad, or low in fermentables(?)

I'm just trying to figure out why this happened to avoid the same thing in the future

Does anyone know if perhaps during the liquid malting process that the temps could have been to high?

I know that when doing all grain, I've mashed too high and had a pretty sweet turnout.

I was sort of assuming that he was using extracts, which should have been mashed under correct temperatures. However, it is something to consider.