repitching aged slurry

I have some saved slurry I want to repitch that will be approximately 3 wks old by time I want to repitch it. I typically repitch within 2 days (at very most) for maximum freshness. I want to reuse the yeast from this next beer I plan on repitch the aged slurry into and don’t want a ton of dead cells in with the mix.

Am I okay to pitch this 3 wk old slurry with no worries providing I have enough cells for my OG, or am I better off adding just a small amount of this slurry to some fresh starter wort and pitching that instead?  If I go the second route, any idea how much to add to X starter size to get enough yeast for next brewday?

You can use a yeast calculator to approximate the viability of the slurry. Try Mr Malty

I don’t like pitching slurry. ??? For the very reason you mentioned.

My vote is make a starter.

done 4 week old with no issues.

I just made a starter for 300ml worth of a 6 month old slury 3 days ago and now it is rocking away in a 1 gallon fermenter with a huge healthy thick krausen

And I have done this many many many times to use for fermentation with good results

straight slurry repitch, no starter?

Yes…many times. Just pitching larger quantity is all. Lags a little longer but no issues.

What yeast? I have had issues with dry yeast slurry apparently because it is deprived of O2…at least that’s what I am told.

830,833,090,001 to name a few.

Sorry ken. I was curious what yeast is in question in the op.

Thames River Valley II WY PC strain released this winter.