Comment spam remains a huge problem for all WordPress users and it is near impossible to completely stop spam software from attacking a website. To completely disable comments is not enough.
Whilst the spam comments are not displayed on the live website, they take space in the database and slow the website down.
Is always possible using some tips to reduce comment spam on a WordPress website. The first steps simply involve configuring the discussion settings correctly on the website going to Settings / Discussion in the main admin menu.
The section “Before a comment appears” in the WordPress discussion settings page allows to control which comments are sent to the moderation queue and are not directly published.
Enabling “Comment must be manually approved” means that no spam comments will ever be published on the website. Moderation can be time-consuming but it gives better control over what comments are published on a website.
A good option is “Comment author must have a previously approved comment”. Once an author has had a comment approved, all of his subsequent comments will be approved automatically.
Hold Comments That Have Links
A high percentage of spam comments contain links. It is possible to send any comments with links to the moderation queue with the “Comment Moderation” section.
Use the Comment Blacklist
The comment blacklist allows to blacklist the IP addresses of spammers who are persistently attacking a website. It is also possible blacklist commenters by URL, email address, name and/or content.
Close Comments On Older Posts and Pages
It is common for spammers to target older articles that have established traffic and a good search engine ranking. So it can be difficult notice that these posts have been attacked.
WordPress lets automatically disable comments on posts and pages that were published a defined number of days in the past.
Install Anti-Spam Plugins
Whilst configuring the discussion settings correctly should be very helpful, there are a lot of plugins available to help when spam becaomes a problem.
The most known plugin for spam is Akismet but there are hundreds of anti-spam plugins available for WordPress. But always be careful. Some of these plugins can hurt the commenting experience for genuine commenters.
The last tip is check the moderation queue and spam folder on a regular basis. Nothing is worse for users than wait a long time for their comment to be approved.