Should I add a Zebrasoma tang to this 'clown-nem only' tank?

[marc price]

I surprised that mine's in a 6' long reef/plenty of open swimming space and no more than two or three smallish fish, hasn't grown much. Judging from the points of reference (clownfish and anemone), in your pic i'd say mine was half the size of yours, Susan B Anthony coin size and six years latter, only around 4". My small 2"-3" Powder-blue Tangs grew to 8" and 9" in less time then that! And i have seen adult Purple Tangs the size of frisbee's!
BTW nice carpet. That photo makes me nervous. I'm amazed at your good luck!
So. getting back on topic and all things considered, imo the best Zebrasoma Tang for his set-up would be a Black tang Z. rostratum. They're generally considered one of the lest aggressive of the genus and don't grow as large as the other less aggressive member's the two Sailfin's.

 

[nanoreefbro]

I think a small yellow tang would be nice in there...

 

[marc price]

...and Sustainable Aquatics has been bringing "Tank Raised" Yellow's to the market which would be even better.
I've seen a few post on Divers Den, so tiny and i like the fact that it's getting a step away from wild. If it were for me, i'd go for it over all others i mentioned just for that reason.