What is a stuck mash?

A stuck mash in your Solo can happen when the filter at the bottom of your basket becomes clogged with grain and no longer lets liquid pass through. This traps liquid in your basket and with the pump on will drain all liquid from your kettle. If your heating element is on and no liquid is in your kettle it can ‘dry fire’ your element which can produce charring of the element (best case) or can quickly overheat your element and cause it to fail completely.


How can I spot a stuck mash?

The liquid level in your Solo basket should not rise during your mashing period . If the liquid level rises at all, you likely have a stuck mash. Stuck mashes typically happen in the first 5-10 mins of mashing  in as the grain bed has not yet set up and the grain is not fully hydrated, thus not fully expanded. Stuck mashes may also occur after stirring. It can possibly occur at any time during the mash. 


How to avoid a stuck mash?

  • Check out our Solo User Guide for our process recommendations on brew day.
  • Each time you open and close the drain valve on your Solo, do so slowly to prevent sudden vacuuming[1] . Only open the valve about ⅛ of full flow 
  • Grain Crush - we recommend a crush of .035" based on our testing.
  • When mashing in, turn the pump off before pouring in your grain. After stirring in the grain, let the grain bed rest 5-10mins before turning on the pump. This allows the grain to fully absorb the liquid and expand which prevents grain from going through the baskets bottom filter.
  • When recirculating, restrict the pump exit valve to about 1/8 of full flow which should result in a slow trickle over the grain bed.


How to resolve a stuck mash

  1. Turn off the pump
  2. Stir the mash for a minute focusing on the bottom of the grain bed
  3. Turn the pump back on
  4. Confirm that liquid level stays the same or drops (doesn’t rise)


Check out the Solo Brew Day Video for more information!