Demosthenes,
Let me make this perfectly clear, I am not an expert by any means, and the following is from what I have read, heard and know from personal experience.
Anenomes are not found on reefs, and are most likely not suited for reef tanks. Some say you need perfect water conditions, strong lighting, and regular feeding. If you plan on keeping anenomes, you should research them extremely well. What are the water conditions where they come from, including average water temperature, depth, current, etc. The amount of light the anenome gets/uses is determined by water depth.
Feeding the anenome could also be a problem. Are we as hobbyists over-feeding them? How often do the eat in the wild? Once a week, once a month? Most anenomes have symbiotic algae which aids in feeding. Is our lighting cycle long enough or of the right spectrum for maximum production for the algae? Until more research is done, they really should not be kept by those of us with little or no real knowledge of their needs.
If you are planning on experimenting or doing research on keeping them, I would suggest the you keep a log of what you are doing. I would monitor the amount of food, water quality, lighting cycles, type of light, supplements, etc. and their survival rates under each condition. Before anenomes are kept, the requirements for keeping them healthy and happy should be known.
I have kept 2 curlique anenomes for several years, and they are still doing well. These do not look like the average anenome that most people keep in their tanks. They look similar to a large aptasia anenome. I have had a flower anenome for about 2 years now, and it is doing fine under 2 40W tritons, and 1 actinic (I have only fed it once).
I also have 2 condys that I have had about 1 year (I did not purchase them, they were given to me when a pet shop closed down.). One is kept under the above lighting, and is feed about once 3-4 few weeks. The other was moved to my 7 gallon nano with a 32W PC light. Both are doing fine. They were both white when I got them, and now their color has returned. Even thought I have them, I do not recommend keeping anenomes.
Years ago, I killed a few of them, including a nice yellow sebae, and have not purchased any since then. More knowledge is needed before we can actually keep them in our tanks successfully. I have read that they can live over 100 years in the wild. I would not consider mine being a success story by any means, not even the curliques. Time will tell as to the fate of the condys, I figure they have a better chance in my hands (or maybe not) than at the pet shop where another inexperienced or unsuspecting aquarist will purchase them.
I feel once we get the proper knowledge on anenome husbandry, we maybe be able to keep them, but as for the time being I would not recommend them. Others may disagree, and may have been fairly successful, but for the most part more have died at our hands than have survived. I hope this has helped.