go with the larger one, i say this for the following reasons
the tanks is fairly large
tangs are messy fish
anthia's usually require quite heavy feeding
and on a side note, are you sure you want damsels in there? 9 times out of 10, they are very aggressive and little terrors in the tank. search around and you will find many horror stories, not only from what they did, but from the reefer trying to get them out of the tank. its your tank and your call, i just want to make sure you know about it..
