do you own Scott micheals book reeffish vol1?
it has a very large section for ID scorpionfish, just remember that COLOR and pattern means very little for these fish, they are very chameleon like.
Second, as always check fishbase.org, type in scorpionfish and go thru the 100s of fish.
I'll make a guess, strictly a guess due to your photo not being close enuf to discern the head, and see any real detail. Its could be an S. neglecta or S macrochair since these are quite common in the hobby. My 2nd guess would be an hawaiian species, like S.Ballieui
Lastly, remember that the care for pretty much all thee species is the same--so having an exact species description is not required
frank