Rapid growing algae

[Hud]

A week and a half ago some brown algae started growing in my tank. My tank is a month and a half old. Everytime I vacuum the sand it comes back in a couple hours. At night when the lights turn off it goes away. I thought it was gone but later in the day it came back. So I turned the lights off for 2 hours and most of it already went away. 
Does anyone know what type of algae it is. It’s brown and it has little stubs like hair but it doesn’t get long like hair algae

[Hud]

I don’t have a picture of it because most of it has gone away

[seabass]

Is it on the sand, the rocks, or both?

 

At this stage of your tank, it's probably diatoms.

[Hud]

Both

[seabass]

2 hours ago, Hud said:

It’s brown and it has little stubs like hair but it doesn’t get long like hair algae

It's "possible" that it's dinos, but there is absolutely no way that we can make an identification without pics.  Even with pics, we probably wouldn't know for sure.

[Hud]

Ok thank you if it comes up again I’ll get a pic of