Any tricks to get my skimmer to start pumping?

I did a partial water change. And the siphon broke on the skimmer that was still running. After the water change I plug it back in but I can't get the pump to siphon water in now. Any ideas? Or is it just a matter of cleaning it somehow? It's a year old and I've never cleaned it?

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The pump is on and trying. But it's not pulling water in to it can bubble and skim

 

Try cutting off the air supply, pinch the tube, and see if the siphon picks up

 

Thanks. Tried that and nothing happens. That has worked in the past though. Thanks for replying

 

You may have to take it apart and give it a cleaning. My thought is it may just be losing power due to detritus/gunk. once you get the pump out, soak it in vinegar for about 30 minutes. Don't forget about it like i did and destroy all the rubber parts of the pump.

 

Think I fixed it. Instead of pinching the tube I sucked air from it. And by doing that it brought water into the elbow and down. Seems like the water couldn't get up and down the elbow. And now it's working!!

 

Yes I think you are right. It's not strong enough to pull water so need to clean.
Think I fixed it but now it's overflowing. Been offline 3 days. Only have 4 fish in my 100g since mostly coral