First time mashing with a 10 gal Megapot and false bottom

Hi All,

I recently picked up a 10 gal megapot (with ball-valve, brewmometer, and false bottom) as a MLT alternative to my 5-gallon beverage cooler. Before yesterday’s batch-sparging experience I had fly-sparged my 5 gallon batches. I have a few thoughts and concerns about my experience to share, and greatly welcome any suggestions.

Yesterday I brewed a pilsner with 8.5 lbs of grain. It was nice to have the ability to step-mash, however it wasn’t quite as smooth sailing dealing with the volumes of the new MLT.

Step 1. Heat the water

  • Brought 7 gallons to 170
  • Drained 4 gallons into beverage cooler to keep for sparging
  • Add 2 gallons of low temp water to 3 gallons in MLT to bring mash water to 5gal @ ~123F

Step 2. Add 8.5 lb grain

  • The resulting volume barely covered the brewmometer. Am I using the right equipment, or is it designed for different batch sizes??

Step 3.

  • Stir occasionally
  • Follow mash schedule

Step 4.

  • Raise to mash out temp
  • Vorlauf - *** I saw LOTS of chunks of grain, and it never really came out as clear as with my beverage cooler MLT. Should I be concerned about this stuff getting into my kettle? Is my crush too small for the false bottom?

Step 5.

  • Collected ~4 gallons of first runnings (tipped the mash tun a bit to drain)

Step 6.

  • Add 3 more gallons of 170F and stir. ** This was difficult, since 2 gallons of that went straight through the false bottom.

Step 7 →

  • Drain for pre-boil volume just shy of my intended 6.66 gal

With my original setup I could easily mash at the usual 1.yadda qt/lb. However, with the megapot the 2 gallons of space below the false bottom simply won’t allow for that volume. I found myself mashing with 5 gal of water just to get the level above the brewmometer. I’m not too worried about this, since BIAB folks are doubling that amount with good results. However it makes me wonder if I’m using the right equipment for the job.

My two biggest concerns are:

  1. Grain particles making their way into the boil kettle.

  2. Dealing with the effects of the 2 gallon space below the false bottom.

As I wrote above, if anyone has any comments or suggestions feel free to let fly.

Thanks,
Jason

The false bottom only holds the grain back enough so the bed is set. You should keep vorlaufing until you don’t get chunks. I don’t know that its your crush, but you can get more/better intact husks if you condition the grain just before crushing.

As for the dead space, I guess I wouldn’t worry about it since you can’t change that. You either make bigger batches or mash with a higher mash ratio. I have done no-sparge mashes with nearly 4qt/lb so I know that doesn’t hurt anything. You may want to let it mash a little longer is all.

Ran into your first problem when I went to a kettle mash tun. I just added more strike water and reduced my sparge. Works fine. I’m close to 2 qts per pound, but no problems.

Excellent, thanks for the feedback. I think I’ll try no-sparge next time since it seems there was almost not enough room to effectively pull off the batch sparge.

Thanks again,
Jason

[quote=“bingbong”]Excellent, thanks for the feedback. I think I’ll try no-sparge next time since it seems there was almost not enough room to effectively pull off the batch sparge.

Thanks again,
Jason[/quote]
Huh? You drain the mash, then add the sparge water. It should come up to about the same volume for the sparge.

[quote=“tom sawyer”][quote=“bingbong”]Excellent, thanks for the feedback. I think I’ll try no-sparge next time since it seems there was almost not enough room to effectively pull off the batch sparge.

Thanks again,
Jason[/quote]
Huh? You drain the mash, then add the sparge water. It should come up to about the same volume for the sparge.[/quote]

I was concerned about having too dilute of a sparge if I added that much water, and then overshooting my total collected volume if I ran it all into the kettle.

i.e. If there were X total gravity points left in the grist after first runnings, then I attempted to get Xpoints/2gal as opposed to Xpoints/5 gal.

I should have checked gravity of the second infusion, come to think of it… might be useful to know for next time.