Nice! That Duncan looks good I picked up a single head and won't seem to get happy like the head is always half open... I know they don't like high light but do they also hate any flow?
Low-Med flow is what seems to be good for me. They like to be fed often too. I have mine in the 'front door' to a rock cave. It started off as one single head. Love this coral. There are also 2 types of ducan. Branching and bushing. Mines a bush.