Every time this question comes up someone posts and says they are doing it with PCs.
Anemones surviving under PCs is more an exception than a rule. Many tank conditions affect the survival rate of anemones, the most relevant of which is lighting. Some people have PCs and other conditions in their tank, most notably a very large amount of free floating food and plankton for them to supplementally feed on that allows for survival.
While I'm certainly not doubting those who claim success, it's important to realize that people generally like to catalog their successes more than their failures, so you are far more likely to hear someone speak of success than a failure, ergo a success story should be compared to generally accepted industry research and standards to determine whether it is a one-off or bonafide fact.
Anemones need food. They get this food in nature from a variety of sources, but the most plentiful food source for them is the symbiotic algae in their tissues that gives them their color. This means that they require light, generally, especially in the case of the most sought-after species such as the Carpet, Magnifica/Ritteri, Bubble Tip, Rose, and Long Tentacle, lots of light.
Having a proper lighting system consisting of metal halides or T5s (due to intensity, PAR, and the fact that you can generally fit more light over a tank) will dramatically increase your chance of success. You can try it with PCs, and you may be successful, but your chances are lower.
Oh, and LFSs love to lie about anemone's lighting requirements. They want to sell you the animal.