I have a male betta that is really sick.. I do water changes every week, I will say I was a few days behind this time around.. I have had no filter in. He’s been in a 2.5 gallon tank and we just bought him a 5 gallon tank, no tank mates yet. What he has been doing is floating around the top of the water and sometimes floats vertically, he is also bloated. His scales look the same not sticking out or anything but I just don’t know what to do or how to help him...