Algea ID

[aac]

I have 2 tanks infected with an algea that I haven't seen before. At a 1st look it looks like cyano, a red slime that is not difficult to remove. But below this slime there is a green/gray algae, very difficult to remove which is growing...
Alkalinity is 10, calcium is 450, no nitrite nor nitrate, mag is 1500 and phos is lower than 0,1.
Any idea or suggestion in algea identification and how to remove it? Thanks!

[Beandawg]

Pics would be helpful for an I.D. If pics aren't possible, generally nuisance algae are fed by excess nutrients. Just because you've tested phosphates, and the results came back low, doesn't mean you don't have phosphates. Phosphates are consumed or "bound" within the algae that it's feeding. You must exceed your phosphate import with your phosphate export to be algae free.