Dettaching movie clips using AS

1

hi there,

i used a tutorial on learnflash.com to attach a bubble effect to the cursor using this actionscript:

var i:Number = 0;

this.createEmptyMovieClip(“canvas_mc”,50);

var myListener:Object = new Object();
Mouse.addListener(myListener);
myListener.onMouseMove = function(){
var t:MovieClip = canvas_mc.attachMovie(“bubble”,“bubble”+i,canvas_mc.getNextHighestDepth());
i++;
t._x = _xmouse;
t._y = _ymouse;
t._xscale = t._yscale = (Math.random()*80)+20;
}

my question is how can i then remove this bubble effect in a later frame in my movie?
I am not familiar with creating movie clips using actionscript so any help would be great.