Harvesting from an actively fermenting lager

Ingredients
1

I have a Helles fermenting that is about 80% done.  That is I am expecting it to finish with about a 75% attenuation and it is at 67%.

I would like to use the yeast again and based on my brew schedule I do not want to wait for it to finish out.

I ferment in a full-sized keg and can use CO2 to push some actively fermenting beer from the bottom of the keg with a racking cane

I was thinking that being that it is bottom fermenting I could push some active yeast slurry into the fresh wort I want to ferment.

Thoughts?

2

Yeah you can do this - the only problem will be that it will be challenging to know exactly how much yeast you are pulling over.  If it doesn’t take off in 24 hours bring some more over.

3

If the fermentation is approaching terminal gravity, you could rack to a new keg, spund that first batch, and harvest the yeast for the second batch.  Just a thought…