10. The water level in the aquarium can be adjusted by using the two top adjustment screws on the
overflow. This is usually necessary once the overflow has been operational for a few minutes. By
lowering the water level in the aquarium you will raise the level in the sump and possibly overflow it.
By raising the water level in the aquarium you will lower the water level in the sump and the return
pump could possibly burn out if not completely submerged. Add or remove water as needed.
11. At certain flow rates, there will be a “flushing” noise coming from the overflow. This noise is caused
by air trying to escape back up through the bulkhead while the water is going down. The enclosed
vent tube will help reduce the level of noise. Place the tube through the small hole in the pre-filter
screen and adjust it up or down until you find the point where the noise is reduced the most. Slide
the small “O” ring down until it reaches the pre-filter screen, securing the position of the vent tube.
Your overflow is now in operation
The outside of your overflow may be cleaned with a non-abrasive cloth. Do not use detergent on any
surface that comes into contact with aquarium water.
Fig. 1
Fig. 2
Fig. 3
