I've been looking to improve my tiny moss pico with a couple of shrimp in it. I read here that Heather Wood is safe to use, so I went to the local park today and collected a couple of dead twigs of it from the Alpine Garden! It's very attractive stuff, I'm looking forward to using it, but how do I go about preparing it? From what I've read, I need to take the bark off? Is this right? Anything else?