Reef Octopus 150 Filling Up

I was changing my filter socks last night and all of a sudden I noticed my skimmer was was filling all the way, rapidly. I shut it down emptied the cup and turned it back on. The bubbles rose rapidly and the same thing happend again, it went to the top and filled the cup again. I didn't change any adjustments or bump the skimmer when it happened. After numerous attmepts to fix it, it just kept doing the same thing. Any thoughts here