Debris and Rigidbody

I have a simple effect set up where when a bullet hits target it spawns three debris objects (small spheres) that fade out over a few seconds. I have made the small spheres physics objects as I would like them to bounce off things. What I would like however is them not to effect other objects physics (IE when I shoot directly at the ground the objects bounce up and hit the character effecting his/her movement). I have made it closer to what I want by making the mass very small of the small spheres, but there is probably a better (zero effect) way to do this.

 

Put them on a layer that your player collided ignores

 

Aye, as novashot said, put them on a separate physics layer, and adjust the properties in the PhysicsManager so the player's layer and the debris layer don't collide.