I think it is cruel to have any kind of tang in less than a six foot long tank. I saw a tank at the local fair last week in a 18 inch tank on display, with a big yellow tang in it, it was sad. Tang's of all breeds are foragers, that like to swim along the reef for miles per day picking along the reef. You must give them ample room to swim and feed in order to be happy and healthy. Unless they are new born, yet will quickly mature and become distressed.
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