Unusual behaviour

[ssherwood]

My fish have been behaving unusually. I have a variety of fish...tiger barbs, clone loaches and others that all act the same way. They perform a very rapid movement, swimming flat, they flick themselves against the edge of an ornament. It appears as if there was something stuck to their gills and they are trying to remove it. Of course there is nothing stuck to them. Has anyone observed similar behavior and found an explanation?

 

[Curtissimo]

Its probably ich!

 

[CRaZeeeBiTcHisH]

that's called 'flashing' and it's usually due to some sort of parasite...if it's ich, you should be able to see little white dots...look up aquarium fish parasites on google and see if anything else rings a bell