thanks gary, your always quick with the good info. the tank is a 4'x2'x2', 120G. i have a pretty adequate skimmer(PM ES-100, a model i think they no longer make), i have a shallow(3/4") sadbed of special grade reef sand w/ some crushed coral mixed in. there's about 90-100 lbs of fiji, and tonga rock, but unfortunatly no fuge. i rarely run carbon. another ? i had is in concern of quarantine, i don't have one set up right now(haven't added any fish in awhile) and i see on WWM that quarantine isn't necessarilly recommended with this genus of tang because of size of Qtank, and diverse diet of the tangs. also because they apparently tend to do well in captivity, and don't tend to be shipped with disease to the extent of other tangs. what is your take on this idea? the BF i would be more inclined to quarantine, or maybe get one from CB.