How big?

[fishoholic]

The yellow tang has been in the 120g for about a month or more now and I tried to add the scopas tang 2 days ago and the yellow tang keept attacking the scopas tang so after 1/2 hour of the attacks not letting up we removed the scopas tang and added him to our smaller tank. Not sure were to go from here, I know our 30g is too small for a scopas tang however he seems ok in there for now until we can figure something else out.