I've seen mine take out a cleaner shrimp one time, never happened agian though and now I have two in my tank. Sixlines are some of the craftiest fish I've ever delt with. I've owned mine for about 4 years, and he's still a small bugger but he holds his own against bulling, though I have to separate him before I add any new fish to my tank.
When I first got him, he was in my then nano reef, a 10g. He was my first fish and apparently I had an abundance of
pods cause he ate so much with in the first day his scales where pine conning. I thought he was gonna die but he was fine.
They like to lay still in the night, they form a mucus sleeping bag and will not nice unless disturbed
I have found these sleeping bags every where, from between rocks to under my mag flow scrubber.