Anemones will annoy corals, that's true. They aren't the best choice for a coral tank due to that and the fact that they have the ability to move, stinging any corals in their way. So, keeping one is a risk you have to decide if you want to take. I've been lucky and keep a few in my reef tank. If your set on an anemone, I would suggest you get it first. Let it get acclimated and settled. After a few months if it seems the anemone isn't gonna move, then situate your corals around that. There is always a chance the anemone will move again and you may have to move your corals again so keep that in mind. But if your tank is stable, you keep up good husbandry and general maintenance, and no extreme changes in flow and lighting ect, the anemone won't be as prone to wandering.