I understand your position on aggressive fish. my 1st concern was to make sure the Lion would be at home in a tank of that size. From what I have read I believe so. I just think they are beautiful. Do you see this as a poor choice for a beginner if it were alone?
No. Lionfish as the only fish in a reef tank are no problem whatsoever as they are totally coral safe. Although they do not do much except hover waiting for the next meal, they are very pretty to look at.