I've that does not work you may need to take a little aquarium water out, to
just above the line of the pvc tube to try and stop the noise. I tried it
with a system they had at a shop. I put my thumb over the tube to stop water
going down and let go after 5 seconds and it made a noise as the water level
was returning to normal and then it stopped.

Mat
"Jon Pike" wrote in message
. 159...
I've recently 'upgraded' my tank to include a trickle filter design.
Basically, two pvc tubes take water in from just below the water level and
carry it down to the sump below. It's then pumped back up to the other
side
of the tank. My question is, how do I make the input less noisy? I put
fine
netting over top, and that reduced the sound somewhat, but now there's a
higher pitched occasional sucking sound. Any suggestions?
TIA

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