The other day I was messing around and putting some DE into my filter. As usual when I finished I opened up the riser on the discharge side of the filter to allow some water to flow back into the filter to top it up. The water flowed back through the diffuser. I closed up the filter and thought not much more about it.
But last night in bed I realised that something here is fundamentally wrong. When I opened the riser on the discharge side of the filter should the water not have filled from the bottom of the filter. That got me thinking that perhaps I have a problem with the mulitport valve allowing water to bypass. Anyway I opened it up today and everything looked ok but there is very little pressure from the rotor onto the spider gasket. How can this seal then? I took a few photos and the other thing is - how do you get the spider gasket out? It seems to be well and trully stuck down there???