So, can you give us some more details? Your attenuation is terrible and there is most certainly a problem. I would advise against putting that beer in bottles.
If you try everything else and can’t get it going again, try some Beano. It’s saved a few beers for me back during my extract days. Others may knock this suggestion, but I’ll bet most of them have never tried it.
I’ve tried it a few times to try to “salvage” beers. I don’t think there was a single one where the Beano made it better than it would have been if I’d just left it alone.
In my opinion, a 1.030 beer is a syrupy dumper. Anything to help it should be tried and I doubt that Beano will bring something that high too low, but if it does, you’re no worse off.
Before taking any extreme measures, you might want to pull a sample and dump a packet of Nottingham in it. If there is any fermentable sugar left, that huge slug of yeast will take care of it in a short time and you can check the gravity to see where it ended up and that should be your target for the rest of the batch.
That was my first thought too, but surely it can’t be off that much. Yeast, picthing temps, ingredients, fermentation temps, we need all that info to help you. For a beer to underattenuate by that much is very unusual. As a guess, possibly your fermentation temp crashed or your yeast was old and unhealthy. Maybe you used 50% oats and didn;t provide enough enzymes to break them down. Just impossible to say at this vantage point, only guess.
That comment just rang a bell! Is the OP even measuring with a hydrometer? If he’s using a refractometer and not performing the ‘alcohol correction’, that could explain what he’s seeing.
I don’t think I’d make a blanket statement like that. For instance, if the OG is 1.100, a 1.030 FG can be entirely appropriate. And my experience is that using Beano can make a beer just as undrinkable as a high FG.
I can make a blanket statement like that because I don’t think I could choke down a 1.030 beer no matter what it started at. Obviously the OP wants to lower it as well and Beano can do that.