This is interesting. I wasn't able to find any solid answer as to whether groups were ok. The most common recommendation I have found is to have one, or 3+. The tank I got mine from had 5, the guy said they had been there for a few weeks and all got along well. No idea how true that is, but they all seemed content. I do see mine flare up at the reflection in the glass sometimes though. I think I'm just going to stick with one in my small tank, though if I ever go bigger, I'm most definitely getting more. This is one of the most beautiful fish I've found. Good luck with yours, wish I had something better to offer.
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