As you most know I’m a noob to keeping coral. My sons system holds about 65 gl with the display around 45 gl. I just recently bought a Salifert phosphate test kit because I never tested for it before. The calcium, alk, mag, and nitrates stay within recommended levels, I’ve been keeping track of them for awhile. I do 10% water change every 7-14 days. Phosphates are up at .1 and holding before and after most recent water change. So from what I’ve been reading gfo would be my best bet for reducing phosphates, they didn’t seem to go down with my last water change. Is a reactor my best bet or will a media bag in my skimmer chamber take care of the problem?