Possible blow off about to happen!!!!!
 

I brewed a Hop-Head Imperial IPA clone (Bend Brewing Co.). Here are my ingredients:

9.5lbs Light LME
1.5lbs 2-row pale malt
.5 lb crystal malt

1.oz Saaz hops (first wort hops)
2 oz Chinook Hops (90 min)
2 oz Northern Brewer Hops (5 min)
2 oz Cascade Hops (5 min after knockout)


2 Wyeast 1968 (London ESB)

Normal brewing process for a 90 min boil, etc...

My question is since I had a calculated OG of 1.075, the LHB guy said I needed to pitch 2 packs of Wyeast 1968 since I have such a high OG. Should I prep for a blow off here soon? I have 5 gallon batch in a 6 gallon carboy. Just stuck it in the closet not to long ago; should I run and swap out the airlock for a blow off tube?


Note:

I smacked on of the packets like I was supposed to and both yeast nutrients ruptured like they were supposed to. But on the second packet of yeast, only one of the two yeast nutrients packets popped and feed the yeast. I couldn't tell till I opened it up to pitch. Is the second Wyeast packet still alright and healthy to pitch?

yes

It's possible. An aggressive yeast might prove problematic. What's your fermenting temperature?

For future reference, i've had a good experience thus far with fermcap, which is an odorless, tasteless liquid drop that will keep your krausen down to about 1" high. It will also prevent hot break boil overs if used at the recommended amount, which is about one drop per gallon of wort.

I would like to state that even though my calculated OG is 1.075, my first OG was at 1.085. I noticed that I was about .85 gallons shy of 5 gallons, so I toped off my fermentator to the 5 gallon mark and took another final OG reading. It turned out to be 1.068... a whole 8 points short of my calculated. Any thoughts on this and how this might affect anything.

99.9% chance your gravity checked out lower after topping off because it is very hard to mix cold water and wort. Like a glass of tea with too much honey in it, the higher gravity wort persists on the bottom. I would just assume the OG is what the kit states it to be.

This isn't a kit that I am brewing. After adding in the top off water, I aerated for about 5 minutes to mix as much of it together.

I would. I had my 5 gallon Dubbel in a six gallon carboy and in less then 12 hours it popped the airlock off like Mentos in Pepsi... Always better safe then sorry.

Unless you mashed the grains to get sugar conversion I'm only getting 1.065 OG for this recipe in the software

Steeped at 153 for 35 minutes in 2.5 gallons. Sparged with .5 gallons of water at 170 degrees.

Ive calculated at 1.078 on a tastybrew.com. Unless I entered it in wrong, but I got 1.078.

Yeah, mashing brings it to 1.075. Unless you used a paint mixer though there's no amount of bucket shaking that's going to distribute that wort though.