I had brevis and some shells in my 125 gal about 4 years ago with lots of diferent cichlids,they held their own great but had to dash into the shells now and then to dodge some of the big guys.I would never do that to them again however to keep a couple pair or 1 pair with maybe one something else would be killer.Stress free.they look awsome with white sand and handfull of shells.Im sure you could throw a few tiny little top swimmers in it too.Good luck,the puffers are a great one too,my parents gave me crap too on this back in the day until I proved to take good care of my stuff without their involvement.Im not sure how old you are but this should be motivating to get a good carreer so you can get a monster tank in your own krib some day,dangit now I want a little 10 gal just for kicks,good luck.