Yeast Starter Overflow.

I have a 2L flask that I make my starters out of. I've made quite a few 1.5L and even one other 2L in that. Never with a problem. Well I did a 2L with WLP001 and the krausen was intense. I kept a good eye on it to ensure the foil didn't come off and it get contaminated. But just wondering, when there is a Krausen overflow, is there a loss of yeast, or is that just excess?

Lesson learned... use bigger flask for 2L.

Yeah a 2L starter in a 2L flask is pushing it. At that volume, the flask is fairly narrow and easily foams up, sometimes making a mess as the krausen exits the flask. It's happened to me several times.

You likely lost a small amount of yeast with the krausen, but nothing I would worry about.