Foaming starter

What's going on with my yeast starter?????
Yesterday I made a yeast starter for a witbier. I used a stir plate and everything was going just fine. About 8 hours later it had foam all the way up to the foam stopper of a 2L flask. I took it off the stir plate to let it rest. Had to leave again and instead of it settling, it continued to foam to the point that it blew of the stopper and the yeast overflowed all over the counter. Did another starter today and for the first 5 hours it was fine and then started to slowly foam. I took it off the stir plate to let it rest. I'm using white labs 400. I did a white labs Irish ale #004 last week and it was fine. Is there a trick to this yeast? I used one cup of DME to two cups of water for the starter.

Correction on the starter mix. Used one cup of DME to one liters of water.

I've had a similar experience multiple times with WLP023.

-a.

My White Labs Belgian yeast blew off my cap and covered the counter as well. I am waiting for some Fermcap-S which is supposed to help. I also ordered a larger flask (using a 2 Liter now - 5 on the way).

I have since started the White Labs Super San Diego and White Labs English Ale...neither repeated the Belgian experience (nowhere near the Belgian experience).

May be the yeast...not sure, but I am seeing the same thing.

(I use 3.5 ounces of DME per liter and yeast nutrient in each starter)

Maybe it is the yeast strain. I did use a yeast nutrient. Maybe I'll bypass the yeast nutrient on my next batch of Witbier. I plan on brewing tomorrow. I also plan on taking the starter off the stir plate for tonight and putting it back on in the morning and then just pitch the whole mix in the batch tomorrow. Thanks for the quick responses.

I use a defoaming agent both when i am boiling my starter in the flask and then when the starter begins to Krausen, it saves a lot of frustration in the end.

I made my Witbier today and used the foamy yeast. I have to wait and see how it goes. I think it will ferment okay but I'm wondering how it will taste. Another thing I was wondering about is the size of the stir bar. When I did a Irish Ale starter, I used the large stir bar and with the Witbier I used the small stir bar. The small stir bar created a very good vortex and the large stir bar worked good but did not create a very good vortex. Just wondering if I got too much oxygen with the small stir bar if that's possible.

Well the witbier fermented just fine in the primary for 5 days. Racked to secondary tonight and is still fermenting but at a much slower pace. Smells fantastic! Didn't taste it though. Got some fermcap-s for the next starter.