Help with texturing?

So I have a muzzle flash but it looks weird whenever I play it with the gray box around it. I simply have a muzzle flash texture and I went to the object data tab in properties and changed it from opaque to add to make the black that was around it gone. But now how do I get rid of that gray box. Plz explain simply cuz I am kinda new to this.

Uhm could be mip mapping … at least that’s what I remember from a tutorial, just try to scale your UVs a bit up.

Oh thx that was simple lol thanks Zykras