I'm not quite sure if he's asking about cycling...damsels were great starter fish back when because they were hardy, and cheap. Most everyone I knew started off with either damsels or chromis, and chromis aren't as nice looking as some damsles. But damsels after sometime become very territorial and aggressive. They have a big attitude and will bully even the largest fish. That is why it is recommended, if you do want a damsel, to add them last. Trust me, I added two three-stripped damsels first and after 8 months I couldn't add anything to my tank. They even killed my cleaner wrasse. Once it's too late, they're really hard to catch in a complete set up. If I were to do it again, I'd start with a couple, maybe three chromis.