Bot Foxfaces are great aquarium animals. They are hardy fishes that are often some of the sole survivors in a tank crash!
Both species are very similar, with the most notable difference being their their max size. The one with the spot (Siganus unimaculatus) can grow to a max size of about 7.9 inches, while the non-spotted one (Siganus vulpinus) can grow to a larger 9.4 inches.
Remember that both fish have a venomous spine, so be careful where you stick your hand!