Since you should pool the pot instead of destroying it, you will then disable it.
There is a convenient SYSTEM transition event that can allow you to do things in the end of a game object's last frame of activity as it's being deactivated.
It's SYSTEM / DISABLE. If used as a global transition, it's fired up automatically in the FSM as the GO is being deactivated.
This allows you to run a bunch of simple processes, but they must all be achieved within this one, last and single frame.
As for the latter request, you have two options:
One pool for pots that have their associated particle systems, or two pools, one of the pots, another one for the particles.