It almost made me give up on fish keeping....but then I got my second wind. After a couple weeks of mourning and tank decontamination. What happened was, I usually keep a hand towel at the back of my tank to prevent splash back from my filters, as my tank has an open back. And I guess one of the cats decided it would be fun to push said towel into my tank. When I saw it next, it looked like a bubble bath. I tried to save a few that looked like they might make it, but....nothing did. I was devastated.