No more than a week IMO, you should see signs of it opening soon. Moderate to high lighting, moderate flow. All of the ends of the coral are individual polyps and will open to feed. It will prob double in size when its fully open, and it will sway in the current. I feed my corals once a week, alternating zoo, phyto and cyclops. I turn off all powerheads and use a sea squirt (turkey baster) type spot feeding tool. I spot feed the corals and wait about a minute then I turn on all power heads and pumps again.