M84 Bohemian Lager stalled

[chrisbjones202]

Hi all, does anyone have any experience of M84 stalling?

I recently brewed a 25l of pilsner based on GH recipy that came out at 10.48. I added 2 packs of rehydrated M84 at 10 C. Initially fermentation was fine and I ramped up to 18 C after it dropped below 1.030 however it's only got down to 1.020 after a week and hasn't moved after another week.

Any ideas what to do?

 

[chrisbjones202]

No ideas? I'm loathed to throw in a knotty after using 2 packs of lager yeast.

 

[chthon]

What was your mash temperature? I brew a bock every year using this yeast, and I always get to my final gravity. However, I brew in the winter. After primary fermentation I rack it of the yeast into a DJ and let it rest for six weeks in a cold place before bottling. So I do not actually know what the fermentation rate is at the moment I rack, only at bottling time.

 

[GerritT]

MJ is not known for stalling yeast, on the contrary: I know them as good chewers. The amount of yeast should be no problem, maybe a few swirls with a sanitised stick could put some life back in fermentation?

 

[chrisbjones202]

Thanks for replies

I mashed at 65 for an hour followed by 75 mashout (grainfather). Water was 2:1 RO with small acid and calcium chloride addition (following Strange Steve recommendation of my water). Brew day all went well. Brewed in fridge with probe taped to FV. Was looking forward to this one following the hastle of getting RO and 2 packets of yeast.

I'll try a stir later and see what happens over the next few days, it's been in the FV 4 wks so don't want to leave too much longer.

 

[cheshirehomebrew]

not enough oxygen perhaps ?

 

[chrisbjones202]

It had a good thrashing with a paddle for about a minute. Some say it's not such a big deal for dried yeast.

I gently roused the yeast last week. Will check it tomorrow, getting nervous how long it's been in the FV now.