57 Ltr Mash Tun Low Extraction Rate

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Hi People
I have very little experierence in all grain brewing but after a Demo at The home of Ross I decided to switch to AG brewing. I followed with great interest the thread that organised a bulk buy of 57 ltr plastic coolers in Brisbane a while ago. I picked up one of these very cheap because it had a broken tap. On inspection it is evident that these coolers do not suit a false bottom because the housing that mounts the tap intrudes into the interiorer of the cooler. I decided to use a manifold and braided S/S filter. I have used this tun to batch sparge on two ocassions with low unacceptable extraction rates. The third time I batch sparged and suffered a stuck sparge and on this occasion to free the sparge I used the S/S paddle I have to stir and free the sparge. The result of this brew is the best extraction I have achieved. After much thought I believe the problem I have is that the wash water is flowing down the side and across the bottom of the tun and not through the grain.
I have three questions I am hopeing someone with more experience can answer for me.

1 Am I right in my conclusion?.

2 A false bottom which would have to be 50mm from the bottom of the tun is this too much dead space under the false bottom?.

3 Anyone have any other constructive suggestions?.

All help very much appreciated
If you are using a slotted manifold. there is no real need to fit a s/s filter to it. Just recirculate the first runnings until the wort clears, then collect the run off. The grain is your filter.
Are you stiring the mash after adding the sparge water in each batch? Then recirculating again before collecting the next batch?

I AG with a 55 litre eskyand found the same problem. The problem is not with the esky but with the S/S braid. I will do a search and find the thread that I started which asked the same question as u. I ended up making a manifold out of 15mm PVC and effeciency went from 60% to 75+%. Give me a minute and I will try and find the thread, as I am sure there were photos.

I cant find it, but forget the false bottom, the easky is too big. To cut a long story short, got the copper or as I did a 15mm PVC manifold just the same specs. as in the Palmer book.
SJW said:
I cant find it, but forget the false bottom, the easky is too big. To cut a long story short, got the copper or as I did a 15mm PVC manifold just the same specs. as in the Palmer book.

I use a 63 litre mash tun with a Palmer type manifold and consistantly get 75%.
I have noted that most newbie AG'ers dont get the maximum efficiency generally due to a variety of reasons.

Some of these conditions can be;
Grain crush,
Temperature of sparge,
Dough balls due to poor infusion tecnique,
Time of mash and loss of temperature, or incorrect temperature,

I agree with SJW on the manifold issue but only for the argument of dead space in the tun which is greater with a stainless braid, but most who use the braid seem to obtain reasonable mash efficiencies.
My personal choice is a copper manifold with the slots facing downward.
This results in good efficiency and very little wort is lost to deadspace.

Keep on grainin'
dicko said:
Dough balls due to poor infusion tecnique,


As Dicko says, this one is common. Can also be detected by some pretty obvious hazes in the finished beer.

One of the best improvements I made in terms of all-grain brewing was to mash-in thoroughly. Take 10 mins if you have to. Stir the mash in a circular motion and occasionally in a careful "upward" motion. Remaining dough-balls get pushed up. Then Just push them against the side of the tun with your paddle to break them up. Cover your mash, wait 10 mins. Check your temp and stir it up a bit again.

Also watch your L/G ratio. Absolute minimum of 2.5lts per kg is recommended. 3 Litres is even better if your cooler has the room.

Enjoy the experience.

Warren -
I'm only doing partials at the moment with 3.5 kg of grain in the mash tun but am having no problems at all with stuck sparges, etc. I made up a square copper manifold to the exact specifications of the Palmer book. Enclosing the manifold in a grainbag ensures that the slots in the manifold are not clogged with grain debris. I have just done a 50\50 Wheat\pale ale mash with no problems at all. Hope this helps. :D

The one thing I read in the "bible" was to move the mash every 20 minutes during the mash. Then when you add the first lot of sparge water move the mash again, then again with the last lot of water. It stops(read- reduces) any channelling of the run off. And I mean move the mash gently, not stirring a cup of tea.
Thanks to all who replied. It is obvious I need to do more research on manifolds. I will let you know how I go.

Thanks alstart
Lots of different shapes and sizes shown at:

Like mine:

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