1.Set the Groundrules Clearly

People respond to being told clearly where the boundaries are. If you are setting up a forum from scratch you can quite deliberately set the character of the discussion, set the language which is to be used and not used and build from there.

Forums with short posts and responses which are composed quickly tend to have more emotional charge and activity which is what you are looking for but can also decend into personal battles which are inappropriate and get in the way of the rest of the discussion threads.

2.Set up an Informal committee to oversee the forum and deal with day to day issues.

We have only once had to deal with conflict within then PHT forum when one coach whoo specialised in health issues started making claims which she was unable or unwilling to back up with evidence. I asked her to post elsewhere in the other health related clubs as she was upsetting the regulars by making telephone calls and being overly enthusiastic in her selling technique. We had no more "trouble" from her after several regular posters made it clear that she would be challanged to produce evidence for everything that was posted.

3.when people refuse to respond in a respectful way be prepared to ask them to leave.

I had one occasion when a heated debate arose between a sceptic and a person specialising in "space clearing" techniques. The debate lasted for several days and was not getting any further forward towards a conclusion. I asked the sceptic to leave the forum as he was dominating the discussion in an agressive and negative way which was restricting useful debates on other topics from being initiated by the regulars. This was basically an attention seeking tactic and was not appropriate to the ethos of the forum