Tetratec Ap200

[Andypalf]

I have a 120L tank and in it a 12 inch airstone that sits just below the gravel. And I have a Tetratec AP200 pumping air through. Now I have the air pump (along with the hood light) on a timer to switch on from 12pm until 11pm.

Whilst rearranging wires, cables etc I noticed that when i turn the air pump off after a minute of so the air stone actually starts syphoning water out of the tank. I have the air pump housed in a plastic box and wrapped in a towel (my attempt at sound-proofing to quieten the pump) and when I opened it up it was very damp inside.

Is my pump faulty or does this happen to others. Any advice is appreciated. Thanks

 

[kewskills]

ive never had that problem, however you should have a one way valve if the pump is lower than the airstone. these can be purchased at any lfs

 

[The-Wolf]

if you situate the pump above the waterline this will not happen,
if that is impossible for your situation, like the above poster said,
you should fit a one way check valve.
they are only a pound or so and any decent LFS should have them in stock.

it is basic physics that water will find the lowest point and if that happens to
be down you airline, it will be the way for it to go.