To me it sounds like a couple issues. First, as someone pointed out, zero PO4 is never good. You need to get in the tank and manually remove as much algae as possible so that you can get a true idea of what's going on. light could be an issue but I doubt it. The AI prime is not an intense light. The number one issue IMHO is patience. The coral may take weeks to adjust, as long as it is not dying just relax and every 3-4 days try to feed it. Make sure flow is off for about 15-30 minutes when feeding