Starters and headspace

Interesting, what greeted me this morning. Doing a starter for a 1.082 IPA, Wyeast 1056, light DME, starter OG was 1.060 (big for big, I thought) and filled to the point in the growlers where they begin to taper. I have done dozens of starters in the past and had little to no krausen buildup, since there are no hops or other particulates, but these babies erupted.

How much headspace do you allow?

I do not have anything to worry about here, do I?

I got tired of cleaning up messes from my starters. So, I replaced my 2000ml flasks with 5000ml ones. Some yeasts (like WLP001) seems to always explode on me. So, no worries anymore. I have plenty of head space now.

Flasks, yes, have to put that on my xmas list