Along with increasing the popularity of Clownfish, that movie could also be credited with popularizing the Blue Tang as well. "Hey look, it's Dory from finding Nemo!" The Pacific Blue Tang is a member of the surgeonfishes and is one of the most active swimmers of the available tangs. They will need at least a 75 gallon tank (284 liters), preferrably larger, to allow for adequate swimming space. They can be fairly hardy once acclimated but will not do well in a tank that has not completed the aquarium nitrogen cycle. You will also need highly oxygenated water provided through increased surface agitation (multiple powerheads) and/or the heavy use of air stones.
This surgeonfish has many different common names including - Pacific Blue Tang, Blue Surgeonfish, Palette Surgeonfish, Regal Tang, Hippo Tang, Flag-Tail Surgeonfish and some others. Hopefully this makes you want to use the scientific name when researching and asking about this fish. They are remarkably colored with black, yellow and blue markings and are sure to bring lots of activity to the right tank.
Be careful handling this tang with a net because they can get caught easily in the net. If this happens, gently and slowly move the net back and forth in the tank water. Eventually they should relax their fins and come out of the net.
They will probably not do well with other surgeonfish, especially other Blue Tangs, unless the tank is really large, 100 gallons (379 liters) or larger. If you really have a strong desire to keep multiples, you can try to introduce them all at the same time, but have a back up plan ready. This tang is one of the more peaceful of the bunch and may get picked on by other tangs that are already in the tank. A lot of territorial aggression can be determined not only by the size of the tank but also by the order of introduction into the aquarium.
They primarily feeds on marine algae and having lots of live rock in your tank will provide plenty of grazing opportunities in between meals. Try to give your Blue Tang a varied diet and supplement their diet with marine seaweed using a veggie clip to prevent the colors from fading in this fish.
This tang should be relatively disease resistant once acclimated but you still need to take proper pre-cautions and use a quarantine tank before introducing them into your main tank. Keep them in the hospital tank for two weeks or so and watch for obvious saltwater diseases, such as marine ich.