Thanks for the comments everyone.
DVS: i plan to add about 30-40 more lbs of LR. i think that will make a nice look and still leave swimming room for those tangs.
Melissa and Nerdy: that boxfish has the best personality of all my fish. he is always following me around begging for food. i would recommend anyone to get one of these if a spacious tank is available
i've had this one for a year now and he's been very hardy.
thanks again all