Multiple Kleins Butterfly Fish long term?

SDguy · Aug 5, 2020

Well, the good news is I have a pair of butterflies. Love seeing butterflies in pairs. The bad news is that it is a result of trying to keep a group of Kleins Butterflies. Two decided to murder the "third wheel" in the span of 36 hours - luckily I netted her out of the tank and she'll recover in the fuge. I've had the 3 small juveniles in my main display (8' 240g) for a few months now. They were added at the same time. Everything was great, until it suddenly wasn't. This wasn't gradual.

This is my first time keeping Kleins. Does anyone have first hand experience keeping them in groups? I thought it was possible, but maybe not in my situation (number of fish, size of tank, etc)?

susan ingram · Aug 6, 2020

I dont know but lemmee give you a bump

SDguy · Aug 9, 2020

susan ingram said:
I dont know but lemmee give you a bump

Thanks. Yeah I figured such a specific question would be a long shot

mitch91175 · Aug 9, 2020

Not from experience but I've read that certain butterflies you shouldn't house together, but you can always try to use a mirror to see if that will help stem off any aggression. That's what worked for me getting a Powder Blue and Achilles Tang housed together.

Essentially you put a big mirror on the from of your tank for a couple days then remove the mirror. Usually fish that have aggression for the same species with be aggressive towards the mirror and not other fish in the tank. The idea is by the time you remove the mirror, the aggressive fish have given up and become a more model tank citizen.

SDguy · Aug 9, 2020

mitch91175 said:
Not from experience but I've read that certain butterflies you shouldn't house together, but you can always try to use a mirror to see if that will help stem off any aggression. That's what worked for me getting a Powder Blue and Achilles Tang housed together.

Yeah I agree, IME most butterflies can't be kept in multiples long term unless paired. But for some reason all the online descriptions for kleins says they can. So I guess I am just curious where that comes from...

SDguy · Sep 12, 2020

So I thought I would give this another shot. The third wheel is fully healed/recovered in the fuge. I acquired two more specimens, both the same size as the third wheel. The two in the main display have obviously grown more, so they are larger than any of the others. I introduced all 3 (two new, one old) to the main display. Not surprisingly, the smaller of the established pair went right back to attacking the third wheel. Much more interesting though, not only did it not attack the other two additions (maybe some slight chasing here and there in the first couple hours), but the two new ones ALSO began attacking the poor third wheel. There is clearly something about that one specimen that the other 4 just do not like. Maybe it's a disease thing, like cancer sniffing dogs, that the other 4 can detect, but is not visible to me? IME fish will often purposely kill off weak individuals in a group. Anyway, back to the fuge, and off to the LFS mr third wheel will go.

mort · Sep 13, 2020

I kept kleins in a group for about 18 months. This was at a lfs and the group grew from 5 to a dozen after a few months when I added more. I never saw any conspecific aggression surprisingly but perhaps that was due to the size of the group.
These were my coral inspection team, with any new corals spending about 15 minutes with them before being moved to the sales tanks. I did this as there is no better aiptasia removing method I've found but they were far from coral safe, hence the 15 minutes (any longer and they started go after the coral.

I've never found a fish that looked better in natural sunlight than the kleins and if I had a fish only I'd definitely try for a group but consider 5 perhaps the minimum. Good luck with yours.

SDguy · Sep 14, 2020

Thanks for the input. We'll see how the remaining 4 do...

SDguy · Oct 27, 2020

Well, just to button things up... eventually the smaller of the pair ended up attacking and cornering the other two newer ones. I removed them, so just the pair will have to do. So, final thoughts - even though most online retailers and informational websites say these can be kept in multiples, I had no success with up to 5, having two pair off and attack the rest.