I am fairly new to reefing. My phosphate levels were perfect until about two months ago. After several water changes my levels were still higher than I would have liked so I purchased a GFO product and used it. Within a few days I had four fish die. I pulled out the GFO. I read more about it and thought that maybe I had used it improperly so I tried it again this week as I was still having issues getting my phosphate levels down. I only used half of what was recommended on the instructions, again I lost 5 fish in three days. I'm heart broken. I have been working so hard on my tank especially this last month. Now my corals are looking a bit sad. I change out my filters weekly, my socks daily, water changes every week. Last week did 5% every other day. I'm at a loss. In tears. Any advice?