Help with Biowheel

I've had biowheels stop because the endcaps on the white spindle in the middle of the biowheel was full of gunk and also because the plastic piece that the the endcaps sit in was bent so there was no free play for the wheel to turn. Oh something else that happened was, the screen/mesh stuff that holds the bacteria was pushed in on one side so the water couldnt fall on that one part and turn the wheel thus making it stop completely. It sounds like you tried everything else so that's all I could think of.
 
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