Pong ball trail: need help!

1

i’m making a pong game and i’m trying to give the ball a trail that blurs and disappears. i gave the trail 30 frames, each one a bit more blurred than the last. the ball duplicates the trail movie clip each frame, giving it a number after the name which increases by one each frame. each frame for the trail has stop(); in it. this is the code i have in the trail:

onClipEvent(load){
	if(this._name=="BallTrail"){
		this._visible=false
	}else{
		this._visible=true
	}
	this._x=_root.Ball._x
	this._y=_root.Ball._y
	frame=0
}onClipEvent(enterFrame){
	frame++
	if(frame>30){
		this.removeMovieClip()
	}
	gotoAndStop(frame)
}

i’m having trouble getting it to be removed. it plays through every frame, but won’t go away. can someone tell me what’s wrong?