I've had some cyano, hair algae, then brown strings with bubbles, and my glass needs to be cleaned daily. It's much better than it was 3 weeks ago (reduced feeding and lighting) but I decided to take control of it and add a gfo/carbon reactor. I checked just now and my new Hanna meter says .03. Should I assume the po4 is locked up in the algae? I'll set up the reactor once I get the one I ordered but I expected to have high readings given the algae growth but the meter reading surprised me.