My dwarf half moon male Betta fish has had this sludge in his tank since the moment I set it up at least a few months ago. He is in a 2.5 Gal which I will be upgrading him to a 10 gal in maybe 2 weeks or so. The 2.5 was just a waiting period tank until I could move my 10 gal back home. I don't...

Please refer to the photo. The white dust-size things are moving around erratically on the aquarium glass and floating on top of the tank. (The bigger white dots are bubbles) At first I thought they were just dusts, but as I look closer they're moving around!! What are these?? Are they harmful...