Bright green algae !! ID Please

[Martinf]

Hi all,

Please can someone tell what this algae is. It's not slimy at all. When you try feel it, it just sticks to the sand. It started a few days ago. I thought it might be the lights as I need to change globes Since a few months but haven't gotten around to it, so I left the lights off but it's still spreading.

 

[zippy]

that looks like green Cyno algae.

 

[Martinf]

So I've been keeping an eye on the algae. It seems to be spreading at night and after the lights are on for the day it subsides. Is this normal for green cyno