Algae in the sand (ID please)

[Bubblebass]

Mats that come back in just a couple of days. Very green. Cover all sand in high and low flow areas
PO4 - .05
NO3 - 30
Run carbon and gfo in a bag in the "sump" of this AIO
Never miss weekly 5g water change in my IM40
Tank is 10 months old
I feel like I have more than enough flow with the pump, 1 380gph pump and 1 800gph pump opposite sides of the tank
Had a larger tank for years, but now with no skimmer, struggling with this stuff
Please ID and recommend a solution
Can't seem to rotate the pics - sorry

 

[skylar]

Try some cerith snails or mexican red leg dwarf hermit crabs. I'm guessing it's cyanobacteria?

 

[vetteguy53081]

It’s cyano. Is tank at or near a window by chance?
Blow loose of rocks with a turkey baster and siphon well
Reduce white light intensity or turn off white lights for 3/5 days. Add 1.5ml of liquid bacteria per 10 gallons during the day and 1ml of hydrogen peroxide per 10 gallons at night for 7 days.
After it clears up, add a few snails such as astrea, cerith, nerite and margarita to maintain control

 

[Bubblebass]

I've only seen red cyano in the past. If that's all it is, I ain't mad about it.

 

[ReefRusty]

It’s cyano. Is tank at or near a window by chance?
Blow loose of rocks with a turkey baster and siphon well
Reduce white light intensity or turn off white lights for 3/5 days. Add 1.5ml of liquid bacteria per 10 gallons during the day and 1ml of hydrogen peroxide per 10 gallons at night for 7 days.
After it clears up, add a few snails such as astrea, cerith, nerite and margarita to maintain control

Doing this as we speak on day 3 of 7 not sure how we will go with this. No coral or fish are affected as of yet

 

[skylar]

Try using a skimmer.

I've only seen red cyano in the past. If that's all it is, I ain't mad about it.

It's green cyano. Try using a protein skimmer.

 

[Bubblebass]

Doing this as we speak on day 3 of 7 not sure how we will go with this. No coral or fish are affected as of yet

Have you seen a reduction in the cyano? I was going to give this a try before chemiclean or slime remover.