Thank you for the prompt reply. It was fine before I start to dose vinegar n all-for-reef as trying to solve the green algae problem. I’m having dkh above 11 since nov, Ca around 480+- and Mg 1360+ after I start the dosing. Did a WC last week, cut the all-for-reef and reduce the vinegar dosing. Will continue to monitor and do wc bi-weekly. Hope the rest of the heads will survive Sent from my iPhone using Tapatalk