Does a strong water current increase gaseous exchange?

[WhiteSheep]

Just wondering if the water current near to the water surface is strong, will that increase gaseous exchange, resulting in more oxygen being present in the water? My idea is to have the current near to the surface strong and the bottom weak (and thus shrimp friendly).

Pardon me if my idea is bad.

[retardo]

If your tank is planted and is CO2 injected, surface agitation is the last thing you want. You want as little current as possible, the reason being that plants love CO2 and will take any dissolved CO2 and turn it into oxygen. Increasing the surface movement only gets rid of the CO2 faster, as you guessed, because it does in fact facilitate the exchange of gases.

If your tank is not planted and not CO2 injected, surface agitation is ok, but I don't think it increases oxygen content by all that much. I could be wrong... It's been a long time since I've taken a science class.

[gnatster]

Current and Surface Agitation are similar yet different.

Current is the flow under the water surface and may not effect the surface agitation. Current is good to a point. I aids in the exchange of nutrients and waste products from plant leaves. It also keep solid matter in suspension allowing the filter to pick it up.

Surface Agitation is water movement on the water - air interface. Generally one would see ripples. This aids in gas exchanges as the surface boundary layer held by surface tension is broken. In turn the O2 level of the water will rise. In a planted aquarium where CO2 is injected Surface Agitation will increase the level of CO2 out gassing and is to be avoided.

[WhiteSheep]

Thanks. Guess it's naive of me. Back to the drawing board...