I am trying to decide on the last fish to add to my 40 breeder/20 gal sump. I have 2 clownfish, a royal gramma and a Vanderbilt Chromis. I would like to add possibly Talbot or Springeri Blue Sapphire Damsels. Which is the least aggressive and should I purchase one, a pair or one of each? Thank you!

they are really peaceful with other fish and you can keep as many as you want. They may bicker with each other, but only at first. They are a really cool shoaling fish too.

