Algea or Cyano - Can't figure it out

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I have either algea or cyano in my 120g reef. The tank is almost 6 months old. Everything was fine until a month ago. The only thing I added at that time was adding a Calcium Reactor. I do a 5% water change every week. My bulbs are 2 months old and run 7hrs. per day. I feed three times a week. I also have a 55g sump with a large DIY skimmer. I'm running a 9W UV and phosphate reactor. In addition to my return pump, I have a Maxi-Jet 1200 which was modified by MJMods. I have a second Maxi-Jet 1200 that is not modified but has the nozzle cut off. The Maxi-Jets are on a wavemaker. Maybe I should take them off the wavemaker and run them continuously...maybe that would help.

I have checked my RO/DI for silicates and phosphates and both read 0 using Salifert kits. My tank water also reads 0 ppm. My fresh mixed saltwater also reads 0ppm.

I have some cerith, nassarius, and astrea snails and a cleaner shrimp. My fish load consists of:

(1) Sm. Hippo Tang
(1) Med. Yellow Tang
(2) False Perculas
(1) Royal Gramma
(1) Six Line Wrasse
(3) Green Chromis
(1) Anthia
(1) Signal Goby
(1) Diamond Watchman Goby

My water params are:

Ammonia: 0ppm
Nitrite: 0ppm
Nitrate: 0ppm
pH: 8.2
Temp.: 79-80 deg. F.
Calcium: 400
Alk.: 8 dKh
SG: 1.025

I'm at a loss as to why I have this algea. Any ideas?

[ct_vol]

I know some people run their effluent through phosguard or phosban to remove the phosphates that are accumulated from their Calcium reactors... If phosphates were your problem, you may have a cyano outbreak...

Algae can't really be avoided, and IMO shouldn't be in a healthy aquarium... Just so long as it is kept in check and doesn't get out of control... If algae is a problem, you might want to think about adding a refugium to remove excess nutrients...

I had a problem with cyano and all of my test kits showed perfect readings... All I did to get rid of it was shorten my lighting cycle to a few hours a day for about a week... And then increased it back to my normal 8 hour cycle by 1/2 hour a day... It has been gone since... HTH...

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I'm going to check the effluent of the reactor to see if there is any phosphate there. I took the powerheads off of the wavemaker to see if that helps. I'm also going to reduce the lighting for a while as ct_vol did to see if that helps.