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Well oxygenated water makes an happy octopus
Although you might be a bit careful with that since (please anyone correct me if i'm wrong here!!) the air that is injected in the water-stream tends to heat up the water slightly. I guess this doesn't matter as long as you don't have very high temperatures in your room or if your tank temperature is already at the upper limit.
Of course this also can have the opposite effect.
I believe nancy once said about the tank temperature that she mostly lets the skimmer (which also works with air bubbles) run at night when the air in the house is cooler.
These are only my thoughts and I don't know if this is really such a big thing at all though
oh yes, one more thing. Many people tend to overlook that a good amount of circulation directly under the waterline (small turbulences on the waterline and such) is responsible for a great amount of the overall gas exchange/oxygenation in the aquarium (the amount is bigger than many may think). So I'd say that if you have good flow of water that breaks up the waterline, further oxygenation might not be a mandatory thing. (still can't hurt though )
You can do it, but it might give you too many bubbles and that could be a bit of an eyesore. Plus the moisture that would get carried over as the bubbles rise and pop would cause a lot of salt to settle on top the tank. If you do try it, let us know how it works out.