I make membership by approval and that stops most of the spam, then I also follow up by deleting members who do spam - for groups that I moderate.
Members need to tell me why they want to join and they usually write things like "I have a BCF 2000", etc. It keeps the bots from crashing your group. Makes the group more pleasant too. I also asked a member I trust to co-moderate, so if I fall off the planet, somebody can keep it going.
Steve
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