How can I enforce online etiquette in a univ forum without stifling dialogue?

[MarkHC]

I'm a teaching assistant for a large university course that recently moved its discussion sections to a public online forum, and I'm dismayed by the decline in civility, with students posting dismissive comments, using aggressive language in debates, and rarely acknowledging each other's contributions. I want to establish some basic online etiquette guidelines to improve the collaborative environment, but I'm unsure how to enforce them without stifling participation. For educators or community managers, what are a few core, non-negotiable rules you've found most effective for fostering respectful digital discourse, and how do you introduce them in a way that encourages buy-in rather than resentment?

[Noah_H]

Keep it simple: start with 3 non-negotiables—no personal attacks, stay on topic, and be respectful in tone. Pin a one-page etiquette charter at the top of the forum and reference it in every welcome post.