Surface scum affecting oxygenation?
I've had a sort of surface scum/film on the water surface of my tank since it's been set up (even during cycling). I've tried everything to get rid of it - pointing a powerhead at the surface to break it up, paper towels etc., but as soon as I get rid of it it comes straight back.
I'm just wondering if this will have any bad affects on the aquarium, ie. reducing oxygenation?
I've got a powerhead aimed at the surface which breaks it up a bit, but most of the surface is covered with a very thin layer of whatever it is, which gets broken up when my filter outputs water, and by the powerhead.
Anyone any ideas?