2nd All Grain Brew & Poor Efficiency (~61%)

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This is what @Bobby_M was trying to point out. This is a flow restriction valve. If it's straight up and down (vertical) there is no restriction and you will be recirculating way too fast and likely get your grain bed compacted.

If it's horizontal, it's completely closed and you'll get no recirc flow. You want it somewhere in between.
 

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I was wondering this too- I did a 5 gallon starting strike water vs 14lbs of grain and the circulation pump wouldn’t function at all. In my first batch I was more like 12.75lbs vs 5 gallons and the pump seemed to work mostly fine with occasional clogs (both had bad efficiency). Curious if maybe I could strike 6 gallons next time and then go down from 3 gallons to 2 gallons of sparging. I considered this but I also feared that would result in less efficiency from less sparge water getting the last of the sugars out.

In addition, my drainage was basically halted at the beginning of the sparge. I put a half gallon or so to start and almost nothing was draining out. I had to use my spoon to loosen up/move around the grain bed in the tun to provide some proper drainage.


When using adjuncts (flaked wheat, etc) you should be adding in rice hulls to prevent stuck mashes. I use some rice hulls even with larger grain bills that don’t have any adjuncts. This Works great in my BZ 3.1 if I’m mashing more than 12lbs of grain. I haven’t had a stuck sparge but I did have a very slow one once before I started doing this. I don’t need any for less than 12 lbs of grain unless I’m using adjuncts. I assume the grain gets a bit too compacted with the higher volume. Some have said that the top plate is the cause. My efficiency is at 72% so I’m happy with my process. I do measure my sparge water with a calibrated pitcher I bought off Amazon and I use .5 gal less than what BF calculates. I almost always hit my predicted pre/post boil OG numbers perfectly but it took lots of practice and adjusting to get to that point. I do mill my own grains as well.
 
Recirculating too fast and compacting your grain bed is going to be a hit to efficiency. Other thoughts:

1. You have a fair amount of wheat and flaked grains in your bill. I didn't see rice hulls listed. With that grain bill, I typically would use around 3 oz of rice hulls. Helps avoid the grain bed compaction issue and thus gives you better efficiency.

2. Wholeheartedly agree with milling your own grains. I used to think it was stupid to spend money on a mill when the shop does it for free. But after several post-mortems on my spent grains in batches where I was low on OG found too many uncracked kernels, I decided I needed to take control of that important aspect and bought a mill. Absolutely no regrets.

3. I agree with @dmtaylor that you're going to get lower mash efficiency with a higher (1.071) target OG. Smart people in this forum have explained the chemistry behind it, but just accept that it's true. If I'm aiming for a higher OG on a recipe, I modify my equipment profile and lower the mash efficiency, so my recipes builds in more grain.

4. I also think the concept @dmtaylor is suggesting of adjusting your equipment profile efficiency to match your results is great advice. I'm sure absolutely everyone that brews all-grain goes on the journey of moving from poor efficiency to good efficiency. If you searched this forum for posts that read "Low OG- HELP!", you'd probably get pages of results. Some people are lucky and it's just one thing they change and they're all good. Others of us, it's a combination of a bunch of things. As you improve things in your process (by reading a bunch of those threads of Low OG on here), your efficiency will climb back up, but it will also become more consistent. You just adjust your equipment profile accordingly and you continue to hit at/near your OG. Or you just leave your profile at 75% and accept all the frustration that comes with several batches of missed OG while you work on your process.
 
I didn’t touch the grain bed. There is just a switch on the left side to turn the pump on. There isn’t really any adjustments. Just on or off is my understanding. All else equal, I did the same thing this time around as last and this time no flow at all after first 10 seconds and last brew consistent flow. Not sure what happened
I have to remember that beginners are not fully familiar with all the brewing vocabulary.

"you're pulling the grain bed down too hard"

The flow speed of the pump is taking liquid from the bottom of the boiler away too fast. It is sucking all the particles of crushed grain down onto itself as liquid tries to get out of the grain basket. It is creating a very CONCRETE-like texture to the grain bed. The grain bed is just another term for the mass of grain in the basket. The compacted mass of grain is just completely blocking off the perforated holes at the bottom of the basket.

In other words, the pump is working perfectly fine. You just have to throttle the flow rate with the blue handled valve on the side of the output pipe that is on the side of the boiler. Fill the boiler up with a couple gallons of water and start the recirculation. Adjust the valve until the flow rate is 1 quart per minute. Get a 1 quart measuring cup and pull up the timer/clock app on your phone. Measure how many seconds it takes to fill the 1 quart. If it's less than 60, you're still too fast.
 
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Thanks for all the tips! I wasn’t aware the blue valve could adjust speed and assumed it was just full throttle or off. Great knowledge to have for the next brew! Ultimately, that may have had some impact on mash efficiency but imagine it won’t be the lions share of the missed OG. It sounds like milling the grain more fine and exploring additives into heavier grain bills like rice hulls could help keep things from becoming “stuck” and preventing proper drainage and flow for various aspects of the brew day. Today is day 7… I took a hydrometer reading and it showed 1.014 today which is great attenuation. My hop schedule was to add the remaining 3.75oz of dry hops on day 7 so I opened up the small airlock top part and dropped them in. To my surprise I saw a thick layer of foam/Krausen and snapped a pic. Everything I’ve read says Krausen usually drops by a few days into the fermentation so I was quite surprised the beer wasn’t done yet, albeit, must be very close. Air lock activity was present but maybe a bubble every minute so I’m guessing it’s at the end of its journey here!

I did decide to open the lid and give a sanitized spoon a gentle stir to get the hops more evenly distributed into the beer. Reason being is when I poured them in, they were all stuck on top of the Krausen layer. Pics below. I do understand this could introduce some oxygenation but I’m okay with it for a one time dry hop.

Curious others thoughts on best course of action for dry hopping and the Krausen situation this many days into fermentation. Thanks!
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