Just as eMail spam is a hated thing in our inbox. You will find that you get comment spam on many websites. Spammers will try to submit information into any form they can find, so they can peddle their wares, websites, services, etc on your website. They hope that exposure will either direct traffic to their website and/or increase links to their website, so to improve their link structure and gain them higher search engine rankings.
While neither of these is likely to happen (for the spammer), it can and will clog up your website, and reduces the quality of your site. So you will want to look for ways to fight comment spam.
Disallow Comments
One to handle the problem is to simply no deal with it. You can, under Settings > Discussion, click on the box that allows people to post comments on new articles and not let people send you link notifications. This essentially cuts off all comments that might appear on your website. Some blogs have started doing this, to avoid management, of the issue, and let it occur on Facebook/LinkedIn/Twitter/Reddit – which are better suited for handling user comments.
Additionally you can turn off the comment section in your theme. However, many of these comment spammers use automated tools, which would send info directly to your website, bypassing the form because they don’t fill it out. If you don’t disable it on the web server, then it will still be processed.
Auto closing Comments
A slight variation of the disallowing comment option, is to automatically close comments after an article is X number of days old. Under the Settings > Discussion menu, there is an option to “Automatically close comments on articles older than”. Then there is a box for you to type in a number. By default this is 14 days, but you can change this if you want. Check the associated checkbox to close comments after a bit. This can be good if you want to cut down on moderation, but still allow people to comment.
If you want to allow a lot of discussion over time, but not “too much” then you increase the number. 30, 60, 90 days allows for a lot of discussion. Most articles discussion dies out after a few days, unless the article is “rediscovered”.
Spam Plugins
While turning off comments makes dealing with spam comments easy, the second easiest is to use a Anti-Comment Spam WordPress Plugin. There are numerous one’s out there, most famously, Akismet, which comes with WordPress by default. (Akismet is made by the same company that oversees WordPress.)
The biggest issue with spam plugins is they will sometimes let spam through, while in other times block legitimate comments. For example, someone my comment with a couple of links to related articles – this is good, but the spam plugin sees it as spammy, therefore blocks it. They can’t judge the value of a link, therefore, they block it.
Luckily, you can block stuff that gets through, and allow stuff that gets blocked, through moderation.
Moderation
Moderation is the process of you manually looking at an email to determine if it is spammy. Often it is needed even if you have a anti-comment spam plugin installed.
Sometimes they don’t appear to be in the body of the text, but the link they provide is. These may get past some spam checkers, but are still bad for you. Likewise, someone who has a good comment, can get caught if they post a link inside their comment text.
To work on this, you will go to the Comments menu option on the left bar. There is no fly out menu option for this, so you need to be careful.
Clicking on that link will take you to a page that lists all of the comments you have received. You can filter at the top based upon Pending, Approved, Trashed, and Spam.
Generally, you need to look only at pending, if you manually have to approve all of the comments, or there is a comment that the spam comment plugin can’t determine.
Hover over the comment, to see what options you have to handle the plugin. (Un)Approve, Reply, Edit, (Mark as) Spam, and (Send to) Trash.
Reducing Comment Spam in WordPress was originally found on Access 2 Learn
