I just got my first anemone a BTA three weeks age, of all the research I've done they are the hardiest and will be readly excepted by most all clown species in the aquarium trade. I have two Clarkis that went nuts when I put it into the tank and hardly gave it time to settle on to the rocks.
The two most important things are lighting and food, the right amount of light is required to keep the symbiotic zooxanthella algae alive in it's flesh and food to keep it from starving to death, you can not solely rely on the clown fish to keep it fed you have to give it additional feedings. I've found that small pieces of squid, silver sides, clams or mussels work ,the more diverse the menu the better.
Be sure to observe your anemone daily noting color and size, size is key and it will tell you how your anemone is doing, if it's constantly moving thats a sign that it's needs are not being met and that usually means a lighting issue.
By the way has anyone out there added an anemone to their tank and have it be the sudden cause of fighting between normally peaceful clown pairs?