Low F.G. from overzealous S-04/low mash temps(?). Thoughts on a fix for the future?

So I brewed what I think is a delicious British-style special bitter, as close to style guidelines (2008) as I possibly could. The color, flavor, and IBU level are all spot-on to what I was going for. The problem is the F.G. Minimum for the style is 1.009, I'm sitting at 1.006. The grain bill and mash schedule are nothing special. 7 lbs Maris Otter and 1 lb Crystal 60*L mashed for an hour at 154*F, then batch sparged. I collected 6.4 gallons pre-boil at 1.035 for 5 gallons into the fermenter at 1.045 after a 1-hour boil. I'm using a 10-gallon rubbermaid mash tun (a la FlyGuy's design) and a 7.5 gallon turkey fryer pot (SS). Anyone have any ideas as to what I could do to up the body on the next batch? I'm thinking of mashing around 159*F, but maybe that's too warm? Will that make my beer a dextrinous goo? :cross:

Any help would be much appreciated!

EDIT: Yeast was Safale S-04, I pitched 2 packets of it.

You could also try a different yeast strain. what did you use this time?

edit, I see you used S-04 now.

you could try raising your mash temp but I wouldn't recommend going all the way up to 159. what about fermentation temp? if that is not controlled and you are fermenting too high, you could get higher than desired attenuation.

Fermentation was in the mid 60's to low 70's. My basement stays pretty constant, especially since I keep the beer against the concrete wall with a blanket over each fermenter for light-blocking purposes. Flavor is fine, so I'm pretty sure it didn't get too hot for the yeast. But you're right, that could be a part of it...What would you recommend as a fermentation temperature for S-04 to keep the FG up a bit?

15C - 24C according to their website: http://www.fermentis.com/FO/pdf/HB/EN/Safale_S-04_HB.pdf

Working yourself up unneccesarily. What does the beer taste like ? Is the body of the beer to your liking? The final gravity reading isn't too important unless the outcome is not what you want (ie beer tastes too thin, lacks body etc). You said the flavour was fine, so is there really a problem? You said you used S-04 - a fine yeast, but maybe if you'd used a liquid yeast, you would not have the same attentaution and therefore a higher FG. There are a lot of variables in brewing and the average shed brewer rarely makes the same beer taste the same way twice.

Why did you pitch 2 packets of yeast? I think one would have been plenty for such a low gravity beer. I just made an imperial stout with an OG of 1.084 and used two packets of S-04 and the FG was 1.015. Fermented b/t 60 F and 64 F. I think your problem lies with pitching 2 packets of yeast.

I pitched 2 packets to ensure a quick fermentation. Wanted to be able to package this quickly ( < 7 days). However, due to work, etc. I wasn't able to get to it for a week. So maybe I should have just left it alone for a bit. And Godzilla, the reason I use S-04 is because it's 1/3 the cost of liquid yeast, so pitching 2 packets (for the reasons listed above) is financially feasible. But, now that I think about it, I may just stick with lower pitch rates for this from now on and leave it for my normal 14-30 day primary, with no secondary or crash cool. Lower pitching rate would probably up my FG, too, wouldn't it...

I dont believe so. I mean pitching rates are extremely important when trying to attenuate a big beer but the OG is below 1.050. So there would be plenty enough yeasties in one packet of S-04. Also you could have just had optimal fermentation (proper temp, enough oxygen) and the yeast attenuated very well. I wouldn't sweat it. Try pitching one packet of yeast next time though and just save the other one.

Mashing higher would surely cause the FG to be higher.

i'd also suggest making sure your thermometer and hydrometer are calibrated/reading accurately. ex: my hydrometer reads nearly 2 points high at the recommened working temp.

edit: reason i'm suggesting this is, though i've never used s-04, the yeasts i do use wouldn't drop to 1.006 if i mashed at 154 and included a pound of crystal 60.