If you have PO4 issues but are color blind you could pick up a Hanna phosphate checker that will give you a digital reading. They aren't expensive and it will help you get a handle on the PO4. You mentioned that you have a reactor, but were running carbon only in it? Carbon will remove impurities but you need to run GFO in it to remove phosphate.
If you have good test kits you can perform the tests, take a picture of the results next to the card, and post it up. We'll gladly read them for you whenever you'd like to test.
The Hanna has been useless for me. I have been fighting hair algae for over a year now (a lyngbya species I think) and keeping phosphate at zero via the phosphorus meter has done nothing. Keeps the sps corals pale and kills macro though.
I have tried absolutely everything that normally kills cyano or hair algae with no luck. Massive amounts of gfo (zero effect), carbon dosing (some effect) lights out, scrubbing, snails (they would rather starve to death than eat it, same with the yellow tang). Only things that eat it are urchins. Last on the list is an ATS or hydrogen peroxide.
