Maintaining clean water condition is always your top priority if you intend to keep your yellow tang healthy. As with any other marine species, deteriorating water condition can easily cause the spread of saltwater fish disease especially ich that can lead to death if treatment does not take place as soon as possible. When introducing your newly acquired yellow tang to their new home, make sure that the pH and water temperature of the tank is close or almost similar to the water in the fish bag or else you could risk introducing unnecessary stress. Usually during this critical period, you will find most of the time, the fish will go into hiding and common problems you will observe is the fish losing color and become whitish. As a responsible owner, you should do your best to closely monitor the water quality and try to maintain the salinity level at around 1.018 to 1.021 and watch carefully for sudden jump or increase in ammonia or nitrite level. But once everything stabilizes, (usually after one to two weeks period), there won't be much problem later on.
One of the common mistakes made by yellow tang owners is to feed them shrimps or krill. The reason why you shouldn’t do that is because yellow tangs are actually herbivorous and they will only accept plant materials and their favorite past time is to nip on the surface of live rocks looking for foods. Certain individuals will even add supplement by adding seaweed, normally sold at pet stores, which will make excellent meal for your pets. Other than that, in order to provide the best care, make sure that you have at least 2 to 3 of the same yellow tangs species so that they will keep each other company (but avoid other adding other tang species such as chevron). In the wild, they always travel in small groups and that’s why it is a good idea to provide the same living condition as close as possible to their natural habitat. In addition to that, you could also add an artificial cave or use an inverted flowerpot to provide them a hiding place so that they won't get frightened easily.
If you are so fond and attached to your new pets, maybe it’s time to choose a name for them.