Hello, people say that water flow from hang on back filters create enough gas exchange for the tank. I just recently installed a filter baffle to the HOB and it now creates a steady stream along the top of the water. This flow does not make bubbles compared to a waterfall like flow. Does anyone know if the same amount of gas exchange occurs or lessens because of the type of flow. The reason why I ask is because I have a small air pump in the tank and would like to know if I still need to run it at all. I posted a picture to give you a better idea of what the flow looks like.