More Filter Weirdness

[FuulieQ]

Okay, so Freedy was really happy for a while with the filter turned off. He blew big bubblenests and I finally got him to flare this morning! But I noticed that the water gets gross in the tank REALLY fast without a filter (2.5 gallon tank). It had developed a bacterial film over the surface. Last time I turned the filter on, he freaked out and got stuck to it somehow, so I've had it off since then.

This time, I ended up changing 50% of the water, putting two layers of pantyhose over the filter and rubber-banding a filter cartridge to the outtake so that it wouldn't blow him around so much.

Is this alright for bettas? Will he be okay with a little water circulation or should I turn it off again?

[FuulieQ]

And are they okay with vibrations in the water?

Anyone? ;w;

[Betta Fish Bob]

Bettas are used to little or no water movement in nature. The current bettas have been bred with long flowing fins that are not as strong as the short, stout ones mother nature gave them.

They prefer SOME water movement, just keep fooling with your filter til you get it right.

Bettas catch disease due to stress easier than a lot of fish, so be careful.

[MollyJean]

I'm wondering how often you change the water in your tank, and if, maybe, just changing the water more often might make up for the lack of filter.

[FuulieQ]

I try to change some of the water every week, but that film on the surface just kept springing back within days. :/

Right now I have it so low that it barely moves the surface, and bubbles on the top get stuck to the sides and don't move either. His fins barely shift when he's sitting still. But I can feel the filter vibrations is I press my hands on the side of the tank.