Before this one i had diatoms (they’re not 100% cleared out but are practically only on the glass, before they were everywhere)
Now this green algae is everywhere and it’s quite ugly.
Pic is a little fuzzy but appears to be green hair algae
Pull as much as you can by hand and reduce white light intensity or the number of hours light is on
Add some cleaner snails such as:
Astrea
Turbo grazer
Cerith
Nerite
12 carribean blue leg hermits
if extreme- pencil urchin
-Are you using RODI water or tap water from the faucet?
-Is tank at or near a window?
-Assure phosphate level is Not elevated.
If you can take the rock out scrub it, and put it back. It will take quite a while to control it but saves any dosing mistakes. In the meantime lower your nutrients