Black perculas and ... ?

[traco]

I can't believe I've yet to get another fish for my 55 gallon .... it's been up and running for over 3 1/2 months now!! So, I figure it should be well cycled. It has around 30 lbs of live rock.

I have 2 black perculas in there and was looking at adding a puffer, either a blue spot puffer or valentini. And maybe a purple firefish also. I was also going to add a pair of sailfin mollies after QT'ing and acclimating them to salt over the space of a month; are they okay in with a puffer? Or will there be nipped fins?

Tanks all.