Regarding the damsels, I'd stick with the Green Chromis(Chromis caerulea). They're not aggressive and you'll find them hardy enough to survive the problems you experienced.
The rest are very aggressive. I have experienced with Glyphidodontops cyaneus. They're very aggressive.
damsels are a typically agressive fish but yet at the same time not depending on age. When damsels are juveniles they are similar to a clownfish and will make an anemone its home, however, as they get older they get to be a bit braver and start becoming more agressive. While some species will be less agressive...they are still agressive. Like blue said green chromis are fairly peaceful however i have found them to be one of the harder fish to keep alive. Once they are established in a tank they are fine but getting them to that point can be a bit tricky so if you do plan to take that route don't be surprised if you lose a couple, they stress real easy.
I agree with Ziek. Most of the damsels do get pretty aggressive as they get older. The calmest you could probably find would be the chromis, although they aren't the hardiest. The hardiest damsels that are also pretty laid back would probably be the kupang damsel or springers damsel. Anything with devil in the name tends to get exceptionally nasty. So do blue velvet damsels.
I avoid all damsels to begin with. Most experiences I've encountered is that they are all quite nasty. There are plenty of other beautiful and small fish to choose from. Six line wrasses and bangaii cardinals are both a lot more laid back and much prettier to look at. I even tell people not to use them for the cycling stage as once they are in the tank they are almost impossible to remove.
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