Filter Position In The Tank

[ant57]

Anyone know exactly how far the filter should be positioned from the water surface to work properly? it's about 5cm from the surface at the moment.

 

[Westwood]

Place it so the outlet agitates the surface of the water. This allows for gas exchange to happen.

Westwood

 

[TomShootsPhoto]

Or, if you have an air intake valve, it could go under water, so air still gets in your tank. It's more quiet too.

 

[OldMan47]

In some of my tanks, I have a filter that discharges several inches below the surface. Fish in those tanks do fine because I have enough flow that the water near the surface does not become stagnant. If you get too close to the surface things get noisy and with 26 tanks running I can't afford that much noise. It would make my house sound like the LFS.