Another filter question...

[Aude]

So, I have another slightly dumb question...is the biowheel fitting in the eclipse tank hoods supposed to rotate around? I was changing my filter out when I saw that it wasn't turning. I poured some water into the filter during the water change and the wheel started turning - and was making such a noise that I had to get out of bed and touch the wheel to stop it so I could get some sleep.

Any ideas?