I can't remember if I even bothered setting one. My app doesn't use them. I don't find them particularly useful on forums anyways. I only like them on real time chat apps where I know I'll be interacting with the same folks over and over again.
Edit: I did set one up!
Don't plant bamboo, it's like English ivy or Himalayan blackberry but worse.
We planted it in a containment barrier. It jumped the barrier and is almost impossible to remove.