Identify this algae, green dust or green spot?

[OSUOKC79]

I've been fighting this algae in my big tank for months! I dose mix my own ferts and dose daily. Lights are on around 9 hours a day. (4 bulb T-5 HO, 2 Zoo Med plant bulbs, 2 10k daylight bulbs) CO2 injection is enough to just make the plants pearl. Drop checker right in the green zone. I've tried starving the water of phosphates for a few weeks and it keeps growing, I've pushed phosphates up above 40 ppm, still growing. Water changes weekly, twice weekly, every other day and it just keeps growing. I have nerite snails that barely make a dent, I'm guessing I would need 100 or so to do much good. There are probably 50 Malaysian trumpet snails hiding in the substrate that come out at night and gorge themselves on it, but it grows too fast for anything to eat it. It grows on the glass, rocks, drift wood, plants, substrate, snails, and canopy. I have 3 tanks, all with the same water source, 2 get ferts, and they all have algae, but this is the only tank that it's a problem. Any advice would be great!

 

[OSUOKC79]

More pics

 

[Hubert90]

I've been fighting this algae in my big tank for months! I dose mix my own ferts and dose daily. Lights are on around 9 hours a day. (4 bulb T-5 HO, 2 Zoo Med plant bulbs, 2 10k daylight bulbs) CO2 injection is enough to just make the plants pearl. Drop checker right in the green zone. I've tried starving the water of phosphates for a few weeks and it keeps growing, I've pushed phosphates up above 40 ppm, still growing. Water changes weekly, twice weekly, every other day and it just keeps growing. I have nerite snails that barely make a dent, I'm guessing I would need 100 or so to do much good. There are probably 50 Malaysian trumpet snails hiding in the substrate that come out at night and gorge themselves on it, but it grows too fast for anything to eat it. It grows on the glass, rocks, drift wood, plants, substrate, snails, and canopy. I have 3 tanks, all with the same water source, 2 get ferts, and they all have algae, but this is the only tank that it's a problem. Any advice would be great!

I believe it is green dust algae. Don't worry too much, it should go away by itself, unless you can stand the looks then remove it with a razor blade (don't use a razor blade if your tank is made of acrylic though).

 

[OSUOKC79]

That was my number one guess, it's awful! I can scrape every day and the next day it's back. Actually if I don't use the mag float every day the only thing that will take it off is a blade. My snails eat some of it, but never really get ahead. How long does this stuff take to run its course?