My Pondmaster pump (190 gph) for my filter kit suddenly stopped working after about one year. I bought a whole new Pondmaster kit with a larger pump (350 gph). I was impressed with the power of the pump for about 24 hours. Then, while moving it today, the new pump stopped working also! For both of these pumps, I took off the cover and inspected the impeller assembly. No damage as far as I can see. Both these pumps still make some noise when plugged in, but very little water is pumped.

Any advice?

I think the impeller may not align or it may stuck somewhere. I had that problem before with my aquaclear powerhead. I tried to disassemble everything and put it back together very careful. It worked after that.

If you heard the noice. I guess you have to straight the impeller.

Thanks. I've already disassembled and reassembled the pump, but it doesn't seem to help. Maybe, I need to read up about how the impeller system works to figure out what might the problem be. Do you actually take the impeller apart? I just removed it and put it back.

I don't know if this may help or not, but when my old aquaclear impeller stopped I took it out of it's slot and cleaned the slot out with a qtip to remove any gunk that was impeeding the proper movements.
Good luck with the filters I hope you can get it figured out

Well, I just want to report back that the impeller was indeed the problem for both of my Pondmaster pump failures! I ordered replacement impellers for both filter, and installation of the new parts restored both the pumps. Now, I have an extra filter kit.