Almost any fish even algae eaters under the right circumstances can become a coral problem. Usually fish known as reef safe if underfed or if socialized with coral nippers can pick up bad habits. If you do a net search on reef safe fish, and read enoeph articles you will see this behaviour exhibited by usually safe fish. I love flame angels but because it is such a crap shoot with corals have elected not to stock one. Also some corals are more appealing to fish than others while other coral have nasty things in their slime that discourages nipping. You just have to do the research and take your best shot. I am restocking a 72 mixed reef with the list below but nothing is certain, just less likely.
1-Two Spot Bristletooth, in QT now.
1-White tail Bristletooth, very different color than the 2 spot.
2-Standard Ocillaris clowns (intro a nem while clowns in QT) Tank age considering QT time will be 6mos.
1-Green clown Goby
Other possibilities are Dispar Anthius, Black Axil Chromis, and the aggresive damsel family in general. McCosker Flasher Wrasse, Some wrasses not reef safe at all so research them. Gobys in general ,
Note: Don't overstock your tank. Select fish based on tank size and carry a light load. Best advice I can give at this point. Don't add 2 of the same fish unless they are schooling fish known to do well like Anthius. I have made alot of mistakes and IMO
the list above is still a risk with 2 totally different color tangs but both tangs none the less and may be a problem. I will just have to keep close watch and act if a problem occurs.