I have had my leather coral for about a yr. It has continuously grown and been well. I have been noticing lately that there are white patches appearing. It is completely open and polyp extension up until yesterday. The only thing changed has been my light. I changed to Ai Prime and did a water change yesterday- the polyps were closed yesterday. The white patches appeared prior to the light change. Does anyone know if this is a sign of decline in leathers? My params: 1.026 78 temp Alk 8 Ca 400 Mag 1200 Nitrates less than 5 Phos 0 I do weekly waterchanges, top up daily, test weekly, everything else in the tank is good.