I finally integrated the anti-spam tool called Akismet into my comments system. Akismet is a third-party app that checks all comments that are submitted and declares them as either spam or not. They use their own methods to run a newly submitted comment through hundreds of tests. If the comment comes back as legitimate then it'll be posted on my site. If it's considered spam, then my site will still save it but mark it as spam so only I can see it. From there I can then go ahead and either delete it, or mark it as non-spam.