When I got my Edge 6, during cycling the pump made a constant grinding noise. I kept stripping the filter and cleaning it, but I couldn't get it to stop. Over time, it got less and less to the point where it was intermittent.

Grrrrrrrrr<pause>grrrrrrrrrrrrr<pause>grrrrrrrrrrr <pause>...etc.

I sent a support ticket to Hagen to see what they thought about it. They sent me a new impeller. When I took the filter apart again, I found the shaft had some rust in it. This thing is only a month old. No way there should be rust. And obviously the replacement impeller doesn't come with the shaft.

I put the new impeller on anyway, and had the constant grinding again. Sigh.

I pulled out the silicone lube I use on rubber seals. It's Haynes brand and made for food processing equipment. FDA approved, blah blah blah. I slopped some on the shaft and put it all back together with the original impeller. The new one looked somewhat cheaper, so I'll keep it as a spare.

Blessed silence!

That's all it took. And silicone lube isn't water soluble, so it should last indefinitely. I'll reapply whenever I strip the filter to clean.

Just thought I'd share in case anybody else wants to try it. The lube I use is around $6 on Amazon, but I get mine from work since we have a division that manufactures food processing equipment.

And here's a pic of it today. Needs to have the water topped off...