Filter sock makes skimmer go bizzerk

[Coralgurl]

I was cleaning out some stuff and came across a new filter sock. Since I'd been lazy and hadnt washed my other ones, thought I'd throw in my sump. Well my skimmer went nuts and immediately started to overflow. I pulled the sock out within a few minutes but the skimmer still hasn't settled down. It's been well over an hour since I did this. It's a vertex sock that comes in the box.

Socks are in the washing machine now. Is just because it's newish??