# Modifying a old pond pump



## Hillbilly Homer (Sep 25, 2012)

i have a old Submersible pond Fountain Pump that has way too much Flow for my 20g tank.

i have tried restricting the water inlet but the pump started to chatter. i am thanking about trimming the impeller. 
:-k...Has anyone tried this?...:-k


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## Michael (Jul 20, 2010)

Try restricting the outflow instead. This is the same as increasing the head, and should not damage the pump unless you completely cut off the flow.

Unless you can get the cut-down impeller perfectly symmetical and balanced, the pump will make lots of noise.


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## Hillbilly Homer (Sep 25, 2012)

Thank you ill give that a try before i tare into it.  Time to go digging in my junk pipe fittings


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## Diana K (Dec 20, 2007)

Better to get the right pump. Too large a pump will contribute a lot of heat to the poor little tank.


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