Fish needed to eat Ulva

[Ordovician_Reef]

OK, the Ulva is spreading from the refugium to the main tank. What fish, or other animal would solve my problem. We have been wanting to add a tang perhaps. Its a 200 gallon currently inhabited by a LOT of coral and to Mandarins. We have a pretty decent clean up crew (Assorted Snails, Hermits, Peppermints and Pitho crab).

 

[KrisReef]

A rabbit fish or a foxface are also very fond of Ulva, and more reliable than a tang ime.