How does this filter provides oxygen

[poothebear]

I have this Juwel BioFilter One filter and I wonder what bring oxygen to the tank? Is this the role of this narrow hose upstair (See video)?

 

[Byron]

Oxygen enters the aquarium water at the surface, and surface disturbance such as that caused by the filter return achieves this. This is the real value of any filter, water movement especially at the surface so the gas exchange (oxygen in, CO2 out) can be effective.

It may also occur with bubbling devices. Any air/water surface, though perhaps not as effective as the actual tank surface.

 

[Colin_T]

The pump in the video has a clear plastic hose sticking out of it. That is a venturi hose and is meant to let air get drawn in and mix with the water being pumped out by the water pump. There is no air being drawn in so the pump needs to be raised up a little bit or the plastic hose might be blocked, or the end of the hose might be in the water.

When the venturi is working properly, there will be a mix of water and air bubbles pumped out by the water pump, and this creates surface turbulence that allows carbon dioxide (CO2) and oxygen (O2) to move in and out of the water.

 

[itiwhetu]

It is all about about disturbing the surface tension of the tank. Think of it this way if there is no surface movement the tank is flat, if you can ripple that surface it then looks like corrugated iron. In effect doubling or tripling the surface area of the tank. Therefore doubling or tripling the capacity of that tank. That is because the gas exchange will be increased so more CO2 and O2 will exchange.