Algae killing Lps and Sps corals

[Oldcoder]

So all my corals except soft corals die from an Algae of some kind that grows around the growth areas. Every time I add a new coral in about a week it shows up around the growth areas. The coral eventually dies. If a dip the coral it this kills the algae and the coral recovers for a while and then the cycle starts. It appears red/brown under blue light and greener if I shine a flash light on it. It only seems thrive in high flow areas. It also appears on the intake of my MP40s. Interestingly the pump intakes eventually get covered with coralline algae and it disappears from that surface far as I can tell not on the rocks. It does grow on the frag plugs. I thought cyno but does not blow off. So does the community have any ideas?? Tank is about 20 moths old.

Nitrate 5ppm Phosphate .02 I dose and test both every other day.

 

[lapin]

A picture without blue light will help.

 

[Oldcoder]

I can not get a picture to attach for some reason in any case all you see in the picture I was trying to attach is tiny polyp in the center with red fuzz growing on the dead skeletons surrounding it where other polyp were.

 

[John08007]

Cyano?

 

[Oldcoder]

Cyano?

 

[Oldcoder]

That’s what I thought won’t blow off.

 

[John08007]

That’s what I thought won’t blow off.

You mentioned

That’s what I thought won’t blow off.

You mentioned it being red. Cyrano is like a red slime that spreads and covers everything. If you vac it out it will come off the gravel in big sheets. Google it and see if it looks like what you have, I'd bet your phosphates are high.