Definitley run some GFO and adding chaeto will help.
Persay my rock has been soaking up Po4 and Nitrates for a long amount of time with FOWLR tanks and now its just beginning to break out because the rocks have been transferred again and again and now that their in my reef perhaps they consistantly leach PO4 into the tank? If that were the case, would GFO and Chaeto cure the problem, or patch it like a band-aid?