Cyano and GFO

Had a bubble algae outbreak a couple months ago out of nowhere. Only thing I changed was filters on RODI unit as TDS was reading 9ppm. Disposed of first 8 or so gallons and did a 6 gal WC on my 55gal tank. a couple weeks later mass bubble algae. Put my BRS GFO+Carbon reactor back online.

I think I started with a bit too much GFO because bubble algae disappeared after a few WC's and couple weeks, but in the past 8 weeks or so I've been battling a lot of hair algae and cyano now. Weekly 15% water changes and 0 on the TDS hair algae is still a problem and cyano is getting worse. Even after dropping the amount of GFO used in the reactor to about 1/2. It's been 2 weeks since I lowered the amount of GFO I'm using in reactor and I'm seeing it more and more cyano,darker and coming faster after sucking it up w/ water changes.

Recap: My tank ran algae free for 1 year. New RODI filters = bubble algae, GFO + Carbon = no bubble algae but cyano and hair algae. Water changes and reduced GFO has no real effect.

Should I just take the GFO out and run carbon only to see what happens? I'm attributing the hair outbreak to reduced spectrum from my year old t5 bulbs, is there a relation with the cyano as well?

Can a complete blackout for 2 days help with cyano and hair without killing my corals? Should I resort to red slime remover?

 

Also added a MJ1200 to the tank for more flow a week or 2 ago. No effect at all. total flow = k4, k3, mj1200

 

Old bulbs maybe responsible for both alga. Two days blackout should not hurt your coral. I doubt the bubble was from RODI change. Check for other sources of nitrate and phosphates.

 

Salifert put nitrate at ~5.. Phosphate is harder to tell honestly because I know the algae is consuming it and my API tests are worthless.. Waiting on the digital handheld unit from tbaquatics to get some more accurate results..

Funny thing about the beginning of the outbreaks are I went on like a 4 month hiatus with the tank where I didn't do water changes, dosed when I remembered to, over fed, topped off way too sparingly and almost lost a couple sps, but my tank was algae free. I got my act together, picked up new filters, ATO, and auto doser and regular WC's. Levels have been stable for a couple months now, clear water, corals look good but a ton of cyano on the rocks only. GHA mostly on rocks, lil bit in the corners on sand.