I have those white flakes, too. I just assumed they were sediment of some sort from the water settling. Kind of like what happens when you melt ice cubes made from hard water - at least, that's exactly what my flakes look like!
I just looked it up and here's what they are: "Melting ice cubes sometimes precipitate white flakes, commonly known as "floaties". This is calcium carbonate
which is present in many water supplies and is completely harmless."
As for your fish's tail and bloating, I don't really know. He could always be biting his tail.