Debris Not Removing

I have a game where objects fall down from the top of the screen, and when tapped they are "crushed". My problem is that even with a delay and remove node added, the debris do not remove and the game very quickly slows down and crashes.

 

Make sure that "is Delta" is not checked. you can find this on the animation node.

 

Thanks Josh - I'll try that out.

 

There is no delta option on the animation node. The debris are still not removing.