Venturi Style Skimmer

The venturi style skimmer uses a venturi valve to deliver air and water to your column at the same time.

This is more advanced than the counter-current style. It does not rely on an airstone for its source of air.

How it works.

Water from your tank is forced, via a pump, into a tube that has a taper on the inside. This taper forces the water to increase velocity. There is a small opening usually at the top of the venturi valve located where the taper is the smallest. The water going past this opening creates a vacuum, thus pulling air into the opening and mixing it with the water.

The higher the water pressure the more air is drawn in and the more air bubbles you will have. This means that you really need a powerful pump in order to have the required water pressure. Some designs have the added benefit of injecting this mixture in a swirling fashion which increases contact time.

Another type of venturi skimmer is known as the Beckett-head design.

This design utilizes a foam generating spray head. This head increases the amount of air that is mixed into the water. Skimmers using this design quite often have the Becket at a higher position than the water level. This allows for an increase in contact time. A Beckett-head skimmer will increase the density and consistency of the foam.

One thing worth mentioning about the Becket design is that the head requires regular cleaning to keep it performing well.

The venturi style skimmer has been around for a while now and many of the skimmers available today utilize this design. It is efficient and can be adapted to most setups.