It's true that many H. magnifica do not survive in aquariums; however, if you get a healthy one to begin with, they seem to be quite hardy. I have a H. magnifica that come November, I will have had 8 years. Although I have tried to maintain excellent water quality, and have for the most part, there have been periods of elevated nitrates and temperatures in the mid to upper 80s . The anemone is doing fine and almost 3 years ago assexually divided. So, you look like you're off to a good start. Take care of it and you will likely have it for many years to come.