The real problem with blue spotted boxfish is they tend to not be good at outcompeting other fish for food, and are really sensitive to disease. The first one I tried, got a mouth sore, which I fixed, then got ick, which I fixed then got some kind of internal problem where he was all swollen and died from that.
The second one, I treated it with hyposalinity and chloroquine phopsphate from day 1, and it did pretty good, it then developed a lymphocyst on the tail. So I hooked an ozone unit to the QT to push the water quality, and with much work got the fish to eat more than just one food. So now we are looking much better and living in the final destination tank with no other fish.