Well that's an odd little story. Right after I removed the crab my last scissortail disappeared. That's it. They have to be transporting over to the carpet in the other tank (who has been blamed for MANY disappearances). I am at wits end. Plotting a complete nuclear restart including the rocks laying in the back drive for two weeks. I went to feed one night and thought... how did that silverside get into the nozzle... oh. It's my scissortail. He had made it into a return, through the three chambers of the sump and apparently was beat to death in the pump before coming back through the return system.