Amount of cells needed

[Brew0ne]

So I always make starters and have been using the Mr. Malty site for pitching rates. I usually repitch yeast and go from the ml needed and not so much the amount of cells needed. So lets say that I need 150 mls of yeast should I make a starter with 150 mls? or should I make a starter with 75 ml and hope that the cells duplicate and end up with 150ml of final yeast volume?

[Quin]

You can reduce the batch volume until you need exactly 100 billion cells, 200 billion, etc. I typically use 7 days after the yeast was pitched for the harvest date (whether it was harvested then or not).

The corresponding slurry volume is what you would need to add to your starter wort. I generally then use 95% viability to determine how big a starter is needed from the "liquid yeast" tab. You can use the slider to adjust how many vials is needed to agree with your slurry volume.