I recently purchased extract for two brews... Helles (6 lbs Pilsner LME, 1 lb DME) and a Maibock (6 lbs Pilsner LME, 6 lbs Munich LME). All 12 lbs of Pilsner LME came in a gallon milk jug. I just eyeballed the 6 lbs for the Helles today while brewing... willy-nilly. Of course, my OG came in low. Only then did I go to the scale.

It turns out I have 7.5 lbs left. That means only 4.5 lbs was used. The problem is this... the "planned" Maibock is 1.086 OG. If I use the excess Pilsner, it will be a 1.097 OG. My concern isn't with the OG, but the FG. This is extract after all. I don't want a 1.020+ FG.

Do I go with 7.5 lbs LME in the Maibock instead of the intended 6 lbs and hope for high attenuation?
Do I wait for high krausen with this Helles and just add 1.5 lb of LME directly to the fermentation?

I did pitch a 1.5 liter slurry of Wyeast 2007 into the Helles and I'm racking the Maibock on top of that. It wasn't totally clean but it was a shit ton of yeast. I don't think a potential speck or two of nasties will get much of a foothold even if I do add LME directly to the carboy.

I would add the extra LME back into the Helles. I think you may be at 1.020 regardless of using extract or not, what is the expected attenuation level of that yeast?

Wyeast says 71-75%, but I tend to have an over attenuation issue. I should get 80-83%. The Maibock will probably be OK with the intended recipe and I'm really leaning towards just adding the LME to the Helles like you're suggesting.

I think I'd be inclined to add it to the Helles, too. Working with bulk LME can be a bit of a pain when you're trying to divvy it up. I get it 36+ lbs at a time (I take a 5 gallon container to the LHBS and have them fill at least 3 gallons so I get the $1.80/lb price). I pour it into smaller (approximately 6 lb) containers at home, then sometimes divide those further. But I always weigh so I know how much I'm using. I'm sometimes pretty surprised at how far off I can be when I try to eyeball it. I think part of it is that a surprising amount can stick to the sides of the original container, so when you think you've poured half, it's a lot less.

Sure, add it to the helles at high krausen...but do you have a way to stir it in to make sure it gets mixed?

I hear ya, bp. I was guessing the bottom of the handle on a milk jug is close enough to half. Guess what...

Hopefully high krausen is enough to mix it a little. I could pour some in now, but at the height of activity just sounds better.

I'd think that even if it doesn't get mixed well, the yeast will still find it. But you may want to boil a little water and add the LME to that. That will thin it somewhat and also maybe pasteurize it.

i'd do this as well. maybe throw some nutrient in

...already doubled up on the Wyeast nutrient towards the end of the boil

OK, done. I added it right in. Boy, that stuff is really up and cranking.