Let's use this topic for ideas and discussion how to stop the spammers, which, to be honest are a real threat to this forum, because if we have to deal every day, with so much spam, it would be very difficult to consider Codoforum for productive projects.

The main website uses drupal. It has many anti-bot mechanisms such as captcha and different honey pot traps. it is currently stops around 15-20 spammers per minute.
but some get through. we are thinking of implementing a throttle mechanism to stop such bots.
Machine Learning based Spam detection will be part of the next release.

What about a Admin-Activation feature for the new users? New Users can registrate, but they should be activated from the Admin/s. I think these should be an option for those Admins who want to use it. An option like this is in SMF too (maybe in other forums too).

Another option could be: allow registration only from users with Facebook account (optional could be Twitter and G+)

Or, respond to a question. This could be a question related to the forum, that only the really interested people could know.

All these could help with the bots, but not that good with the Human spammers. The best way for me is the "Admin-Activation" feature. From my experience the spammers and bots use email addresses that are very obviously only for Spam purposes.

Just my 2 cents.
Cheers

I hope the devs will optimise the automatic and machine-learning spam detection, because as it is now, it is very stressing. In a normal community forum these kind of problems would drive the users away. When multibillion companies like Google/Youtube or Facebook, can't solve the spammers problem with machine-learning spam detection, a small team like this of Codologic can't never ever achieve something like this.
But dear Devs, you can at least deactivate the automatic spam detection for the active users: the old users, users with a lot of posts and topics and so on.

I have another suggestion: What about a Report button for topics and posts. In active communities there are in every moment users around that could help to keep the forum clean from spammers. You can use the permission system for this. E.g, only users with 100 posts and above have the permission to use this button. And the flagged topics or posts won't be deleted, just made invisible, until an admin is online to give a definitive decision.