I noticed this flake stuff on the surface of my tank before I put my fish in and figured it was dust from the new gravel. (I rinsed the gravel many times before putting it in.)
My fish has been in there for a week and is acting fine, but I am a little concerned about this stuff on the top of the water's surface. I just replaced half the water in his tank yesterday and the stuff is still there (it came back). Is this normal? The tank is 2.5 gallons and unfiltered.
(I think I asked about this before but I didn't have a picture. Sorry for a repeat if I did! Could this stuff just be there because there's no water flowing?)