Secla wrote:Right so if I go straight from 1-3 and the final starter actually has to be 3 litres !
I was considering a stir plate but most of the reasonably priced ones only work for up to 1l !
I was planning on decanting and adding to a portion of my stout wort to pitch so at least I got that bit right
Well the online calculators will generate some sort of guesstimate in terms of cell counts, but stepping up by 5 to 10x is the important bit I think, maintaining a balance of 'growth' and 'health/vitality' in the yeast. It may be worth plugging your numbers into something like the Brewer's Friend calculator, but keep the 5 - 10 thing in mind, and the fact that you want healthy, unstressed yeast, in well oxygenated wort each time.
My stir plate hasn't seen action for some time. I tend to do a 1 to 2L 'shaken-not-stirred' starter for anything under (say) 1.070. Any bigger now, and I'd either do the first 700-1000ml on the stirplate (or S-n-S) and the rest in a DJ or 5L Ashbeck bottle, shaken as much as possible. It's been a while since I did a big beer, but the 700-3500ml regime used to work well for me in tripels.