I just got done losing 38 tiger barbs in 2 days to a very nasty RTM. She didn't even eat her kills just killed them to kill them. I rehomed her, and the two remaining tiger barbs I have are doing just fine. The next time around I'm only gonna add a few at a time and see which dithers my fish tolerate. Seems different fish tolerate different dithers.
Not to court controversy, but you really couldn't have moved the tigers out; before 38 got killed?