Hello. I have one male betta in a 1.5 gallon aquarium that I keep in my class room. I change the water every week. He is very active and eats will. I changed his water Friday, September 9. When I came in this morning, Monday, September 12, he swam up to greet me as usual. I noticed right away that one eye has a bubble over one eye. He did eat normally this morning. Friday I did notice that every now and then he would stay in the upper corner of the tank, but when he saw movement he would move around. Other than that he was swimming in and out of his house. Today he is staying more in his house or in the upper corner of the tank swimming occassionally. What can I do? What would cause this in a fish alone with good water conditions?
Thanks!
Thanks!
