How do I pool a bullet in libgdx ashley ECS approach?

Question

I'm having problem creating bullet pool in ashley ECS approach, because i'm using PooledEngine, everything is pooled. So I've done is I just use engine.createEntity(), engine.addEntity() and engine.removeEntity() to spawn a bullet. The problem is, the bullet is not behaving properly. In this memory-management bullet pool example, is working properly but not in ECS aproach. Can someone give me a brief explanation how do I pool a bullet in ashley ECS approach?