Aquaone Cf-1200 Filter

[JasonandJill]

Hi all, for some reason I felt the urge to check the flow rate of my CF-1200 cannister filter and it's only around 450l per hour. The tubes are only a couple of months old, I removed a lot of the filter media to recheck the flow and it made no real difference. I gave it a clean inside (impeller shaft etc) but still no improvement. I've always bled it as per the instructions.
Has anybody else had this problem, or got any suggestions please?

 

[JasonandJill]

One week on and I still don't know what the problem is. I don't know much about how they work but there's an impeller type thing attached to a shaft that sits inside a magnet.
I'm thinking that maybe lubricating the shaft with KY or vaseline might allow it to spin more freely and increase water flow?
ANY ideas? At the moment putting my fluval 3 in the tank would be more pratical!!!

 

[OldMan47]

A few things to check to improve your flow rates.
1. Make sure the impeller magnet and the well it sits in are spotlessly clean. Use a test tube type brush to really clean the well it sits in. A small speck of dirt there can almost stop the impeller spinning due to the tight clearances involved.
2. Check all hoses for obstructions. I recently resurrected a filter I thought was dead by finding a small plug of dirt in the hose near the inlet of the impeller. It was completely hidden until I turned the inlet upside down during cleaning and thought I might have seen an obstruction. A few minutes experimenting in my bathroom sink told me there was a plug there somewhere. All I had to do was find it.
3. Make sure the polishing filter is either new or very clean. That is the thin pad usually closest to the pumping system. A polishing filter pad is great at removing the finest of particles but can also completely stop water flow when it gets even slightly dirty.