Cholla wood prep
I choose to boil mine for about 5 minutes - just as a safety precaution. After boiling, I then put it in cold water to cool it off. After that, I put it in the tank. There must be something that boiling does to it, because when it is cooled and goes into the tank, the shrimp just pile on to it - like 30+ at a time. They just swarm it.
The reason I started this regiment was I went through a nymph episode in my 33L tank. Luckily, it was just one critter, and at the time I had no idea at all what it was. I saw it attack one of my shrimps, so I quickly got the net and scooped it out. This was probably a year ago or so now. It wasn't until a few weeks ago and reading about other people's experiences that I realized what it was that I had back then.
Anyway, the closest thing I could attribute the nymph to at the time was some cholla wood that I had added, and so as a precaution from then on, I started boiling it before adding it to my tank.