What is the clear plastic tube included with my Internal Filter - Venturi. Why do I need a Venturi?

Included in most of our internal filters range is a venturi aeration nozzle and it is supplied help create bubbles and increase oxygen levels of returning water. 
Note; You can only either use the spray bar or Venturi aeration nozzle, not both together.

As water is pumped back into the tank, it can also be aerated by a venturi pipe. This accelerates the water flow and draws in a stream of air from above the surface though the black nozzle which can be opened and closed to increase of decrease the bubbles.


A venturi is a simple device consisting of a plastic tube with a control valve at the top. When a flow of water is applied to one end of the tube, though the filtration pump, it creates a vacuum sucking air through it. The air mixes with the outlet flow of water from the filter and passes into the aquarium. A venturi is simply a device designed to oxygenate a flow of water.
 
Oxygenating the water is important because:

  1. Fish need oxygen to breathe (fish extract about 80 percent of the oxygen from the water that passes over their gills)
  2. Plants need oxygen at night for cellular respiration and to help photosynthesize.
  3. Beneficial bacteria need oxygen to break down (oxygenate) waste.