Split impeller

[fencer]

check the internal surface of the pump for wear. You could get a sedra pump to replace it

[mike31154]

My opinion would be to go with a new pump as well. One with a better impeller design. Even if you can source a new impeller for the current pump, the same thing will eventually happen down the road. I had the same thing happen with a penguin brand power head I used mostly for mixing NSW. Seized up on me. I haven't bothered trying to repair it, it's a relatively cheap powerhead.

Here's a photo of what that impeller looks like after the plastic outer cover for the magnet failed.



It's quite likely the inside of your pump where the impeller runs is scored & damaged. Might be minor but why risk it.