(not from the net!)
I guess I got lucky with my six line. I've had him for about two years and he has never attacked any additions to my aquarium. He lost an eye to popeye (that's what another told me it was called). So he's been my one eyed wrasse for about a year now. It's cool to watch because now he does circles around rocks, searching intensely. OK, now to my point. I have another great thing to add about the usefulness of a six line. I had those tiny worms that eat corals. It was on my Christmas tree rock (which is my favorite piece), and on another coral. The white trails they were leaving on my corals as they ate them were killing me. Every day they got bigger! Then, they stopped. I saw a new spot on one coral this morning. As I watched it for about an hour I finally saw one of those worms poke out and looked like it was looking for a new place to start eating. As I sat there trying to think of how I could catch him and kill him, I saw a flash of purple and green. Before I could even blink the six line had swooped in, one eyed and all, and sucked that coral eating worm right off the rock. So my one eyed, six lined wrasse is now a coral protector, amongst his many other good deeds. I will be sad when he goes.
I introduced a six line wrasse to my 570 liter reef tank in November 2005. I observed him constantly buzzing around the tank, adding a nice splash of green and red to the aquascape. In early February 2006 I went on vacation for two weeks. I never saw him again after I returned. I presumed that it's mouth was too small for the pellets I had used in my automatic vacation feeder and that he had starved to death. I almost bought a new one, except the guy in the store couldn't catch it. It was a good thing, because on June 20 2006, while feeding my fish, I was amazed to see my six line wrasse swimming around and eating. I can't believe that he was there all that time without being spotted through my daily observations and twice monthly water change and maintance procedures. If your six line wrasse goes missing, make sure it really is before you replace it.
I have a Pseudocheilinus hexataenia together with an Ecsenius frontalis. I must say that, contrary to many descriptions of aggressive sixline wrasses, mine is the most placid and docile fish I have ever had. One time have I seen it try to show of to the frontalis, but the blenny casually spred its fins and that settled that argument. I´m now thinking of adding a flasher wrasse (I do like wrasses). Seeing how nicely behaved my sixline is, my hopes are that it won´t harm the flasher, despite its reputation of being hard on other wrasses.
I have a Pseudocheilinus hexataenia as well, and observed it clean the Cryptocaryon parisites off of a C. bispinosus that I had in the same tank with it. I have not noticed any aggression out of this particular wrasse, but I would hazzard a guess that if all these individuals are cleaning other fish, then perhaps it is a part of their behavior.
I recently purchased a six lined wrasse for my small 150 litre reef tank. Once introduced, it was my royal gramma that was attacking him, not the other way around. Even one of my larger yellow tailed damsels had a pop! Once they sorted out their territory they settled down quickly (a day or so), however he has gotten quite defensive due to all these attacks and now, if anything swims too close, he has a wee pop, but overall he doesn't seem too aggressive. I haven't added any new tank mates after him though, but hopefully he'll be OK as I plan to get a few more fish.
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