| Scooterman thier are a couple of ways to look at the problem. Remember zoox are brown (99% of them are) . if the coral is going brown you have to much zoox, since zoox is algae it must be getting fertalized. if it going white or clear you have a lack of them. if its just the color of the coral..say losing its green color, that means that the pigments in the coral are lower and a whole different story.
take care
Mike |