Weird film on top of water?

[hmckin20]

I keep getting this weird film on top of my water, in all of my (unplanted) tanks. It doesn't seem to affect the fish but it looks gross, and I can't seem to get rid of it..

Any ideas what it is? Or what I'm doing/not doing to cause it?

[Tikibirds]

I have it too but only in the two tanks with the live plants...
no idea what it is though. I though maybe something from the gravel? or plants?

[Abby]

its bio film. just not enough surface movement i had it till i put a third filter on my 2 foot (dont laugh the 3rd was new and needed to be seeded so i needed the two smaller ones off the 2 pulled down 5gals to be good enough lol)

[SnowySurface]

That's the thing that bugged me about that bio-film. My bettas don't like the surface of the water to move alot but I don't like the film that forms when the water is still enough for them. It drives me nuts. >.< Now I just let the water surface move a bit without being bumpy and rippled by the filter. I think they are used to it now since the flow from my filter is stronger but not strong enough to make a real current. >.>

[hmckin20]

IT'S ICKY LOOKING, lol. yeah my bettas hated the current from their filter.. stressed them out twenty four seven :C so i took their filters out and have just been doing daily 20%-30% water changes (on four ten gallons and one two gal x_x)