Then new forum moderation

[Vladimir Panteleev]

On Saturday, 22 September 2018 at 19:09:24 UTC, bauss wrote:
> But what is there to stop a spammer from doing the same?

Spammers are not going to exert that much effort in order to be 
able to spam 1 website, so that the moderators then change their 
algorithm and block them again.

This is the key. Spammers win by targeting classes of websites 
running the same engine, or using generic bots that detect 
arbitrary forms, or employing humans to do it for them. To defeat 
them, you must pose a challenge specific to your website, so that 
people who are not interested in your website's topic will have 
difficulty solving, but not the other way around.

> I would suggest some real captcha software that are used by the 
> majority of sites.

No, those work MUCH worse than the above.