I have a 20g tank with 5 white cloud minnows, 4 neon tetras, 1 ghost shrimp (the other 5 died for some reason) 1 molly, 3 albino corys and 2 pepper corys.
One of the 3 albino corys spends 90% of his time at the surface while the other 4 spend their time on the bottom forging for food. When I say "at the surface" I dont mean just in the upper regions of the tank I mean hes compleatly vertical and swimming hard at the surface to get his mouth out of the water. At first I thought there wasn't enough oxygen in the water but non of the other fish stay at the surface. He goes up and swims hard at the surface for 10-15 seconds at a time then swims down and blows a few bubbles. He might forage for food for about 10 seconds every minuet but he'd much rather spend his time at the surface. I dont get it. Even at night when all the fish are sleeping he's the only one still moving around, swimming hard at the surface. Maybe he's trying to fly?
But in all seriousness why is he doing this?
This evening I moved him and the other 4 corys into my 90 to try and get rid of some of the algae, but his behavior hasn't changed at all. There's nothing wrong with him as far as I can tell. He doesn't seem to have anything wrong with his swim bladder. Why is he doing this?
One of the 3 albino corys spends 90% of his time at the surface while the other 4 spend their time on the bottom forging for food. When I say "at the surface" I dont mean just in the upper regions of the tank I mean hes compleatly vertical and swimming hard at the surface to get his mouth out of the water. At first I thought there wasn't enough oxygen in the water but non of the other fish stay at the surface. He goes up and swims hard at the surface for 10-15 seconds at a time then swims down and blows a few bubbles. He might forage for food for about 10 seconds every minuet but he'd much rather spend his time at the surface. I dont get it. Even at night when all the fish are sleeping he's the only one still moving around, swimming hard at the surface. Maybe he's trying to fly?

But in all seriousness why is he doing this?
This evening I moved him and the other 4 corys into my 90 to try and get rid of some of the algae, but his behavior hasn't changed at all. There's nothing wrong with him as far as I can tell. He doesn't seem to have anything wrong with his swim bladder. Why is he doing this?
