Surface foam

[ScubaSkeets]

Hi folks!
A day or so ago, my protein skimmer started to produce foam on the surface of the water. Not the microbubbles that are sometimes present in the water, but actual foam on the surface. Before this, it was building up bubbles in the chamber doing its thing, but now its doing this:

Any ideas why?

Thanks!

 

[mdb_talon]

Have you dosed anything into the tank recently. Some medicines/chemicals can cause that

 

[ScubaSkeets]

The only thing I did was take one of the fish out and put him in an ich-x bath, but the returned him (not the bath) back to the tank. Surely, he couldn't have has THAT much Ich-x water on him to cause that, could he?

 

[CoralNerd]

Do you have a clogged airline or loose part perhaps