Why is my skimmer going nuts?

[kien]

I would just let it overflow for a few more days as intarsiabox suggested. I don't know what it is but clearly some reaction has occurred in your tank. Another suggestion is to simply raise your skimmer a few inches. Create a shelf out of egg crate or PVC tubes. This will help with the overflowing and should allow you to adjust your skimmer water level better.

I've found that if a skimmer is too deep in water for its own good it can be more susceptible to overflow. Raising it can give you a larger margin for error and adjustability.