Having too many may result in them attacking other animals. :thinking: I dont know that for a fact.. but it would make sense.. if you had like 20 in a 55 gallon or something. I have 4 in a 55 and that works well.
I bought 10 off of SWF.com for my 75 reef had some aptasia and they cleaned it out in two days and all of them are growing and doing fine in the reef. I do have about 125 lbs of rock and tank has been up for 14 months. I would not put more than 10 I really only wanted about 5 but the 10 was a good deal and my lfs will buy them from me if I start having any trouble. It's nice having them because if you overfeed they clean up for you.
well, actually, that is not totally true, in fact they are not good in intermediate groups, in LARGE groups, they are actually better than intermediate groups, I guess I should have been more specific.