And Then There Were Three

I must be a really bad aquarist. Today another of the fish in my aquarium passed away. My albino tiger barb had not been looking well for the past few weeks, and it especially seemed to go downhill after my two remaining tiger barbs started disappearing from the aquarium a few weeks ago. This evening I noticed that the black-banded leporinus was really going after the albino fish. He was really digging into it. While drying dishes this evening, I noticed that the albino tiger barb was swimming upside down. It was still alive, but I knew it wouldn't last long. And indeed, within a couple hours, the fish was gone. So now I am left with the black-banded leporinus, a red-tail tinfoil barb, and a plecostomus. I'd like to get some new fish, but that won't happen as long as these remaining fish survive. Any new fish would be too small to introduce into an aquarium with these larger fish.