Something funny about my Hallucination zoa

[SR Reefing]

I have a disk of hallucination zoa grown from a single head 2 years ago.

Couple month back, I realized that they have developed 2 different color on the same disk. They all the same zoa, grown in my tank.

So what do u guys think, is it because the difference in par level, as the more orange ones gets more light?

Or it's because they are new heads, when they gets order they will change back to darker color?

 

[Saltyreef]

Newer heads. The ones in the center mature halls.

Lighting also plays a role tank to tank.
Heres my old frag.