Control how particles are removed from the Particle System.
| Disabled | Particles are removed when their age exceeds their lifetime. |
| PauseUntilReplaced | Particles are removed when creating new particles would exceed the Max Particles property. |
| LoopUntilReplaced | Particles are removed when creating new particles would exceed the Max Particles property. Before being removed, particles remain alive until their age exceeds their lifetime. |