Actually if we are talking about the Heteractis magnifica, aka Ritteri or African anemone then this one is rather common. They can get rather large so if you get one plan on having at least a 55 gallon tank or larger. The common ones are brown but they can occationally have red or ruddy colors leaning to purple.
Even in the wild, as well as home aquariums, they often go as high as they can get to get as much sunlight as possible, so in your tank they would prefer metal halides. All to often there are reports of them going up the sides of the glass and haning around the return water supplies which is not a good thing. They also prefer stronger currents so have plenty of water movment. These guys can also catch and eat smaller fish.
My preference would be Tank raised BTA's or RBTA's.
Thomas