Okay so I have had 6 rummies for about three weeks. They were all great except one, he wouldn't school with the others. He just hung out by himself. He still ate and all, but just didn't fit. Tonight, I found him dead, but the others look great. I am sad for him. He didn't seem sick at all.........have you all had this happen? Nitrite 0 and Nitrate almost there........no ammonia. Temp 77 degrees.........55 gallon on my sig........