Does anyone else use the Fluval U2 filter? I've been running a second hand one a few months now and the venturi valve has never worked. Today the filter packed up so I went to my LFS and bought a brand new one and the venturi doesn't work on that either. Is it a design fault? I have a U3 in my other tank and that one works fine.
I have one although don't currently use it (as it was a bit bulky for the smaller tank I now have). However, its venturi kept dislodging itself, so I didn't bother using it - the filter outflow does a perfectly good job on its own, without this optional feature.