What is this

[reeflife75g]

What is this the rest of my tank don't have it just in my sand ? I can stir it up and it comes back every day ?

 

[Ludders]

Looks a bit like dinoflagellates at a glance.

 

[Jose Mayo]

By the coloring seems to be dino.
Click in the thread below, there is enough information there.

https://www.reef2reef.com/threads/dinoflagellates-–-are-you-tired-of-battling-altogether.293318/

Regards