10 gal is too small for host anemones. Even too small for a pair of clownfish. I would avoid these, unless you invest in a larger tank, and after you keep reef tank for a while. "How old is the tank?" is only smaller part of if you should put an anemone in it. The larger part is that you should be a moderately seasoned reefer before you should attemp to keep anemone. At the very least you should be able to keep the well keep, stable reef tank. Definately host anemones are not beginner animals and you are a very new reef keeper (my guess from what you wrote)
Stable condition is what anemone need. How old the tank is is not the right question in this case. "Can YOU keep a stable 10 gal tank reeftank?" is a pre appropricaate question. Many reefer, myself included, got hook on reekeeping by seeing anemone and clownfish. I killed my first anemone in 1980. I hope you take my advise and hold off on getting them until you keep a well run reeftank for at least 1 year.
