I have a 10 gallon tank with 8 Serpae tetras and 3 Otocinclus catfish (maybe just a tad bit overstocked). I have tested the tank and the water is under safe parameters. I recently noticed that most of my Serpae tetras weren’t going to the surface to eat like usual. Open closer inspection, I discovered that, every time a tetra would go to the surface to eat, they would get scared off by the same tetra. The part that I find weird was that no other Serpae tetra is being aggressive in any way, this one just decided to chase off the other fish while feeding. Because of it, the other fish are not hardly getting any food. They will nibble on the algae wafers for my Otocinclus catfish, but I am concerned that they are not getting enough food.