Any way to stop spam comments from showing up over and over

I am using Akismet, and have Blacklisted the person’s name as well as email. But the spam keeps showing up in the spam section of the dashboard. I’m wanting to know if there is a way to eliminate these altogether. As it is now, we’re getting an average of 50 or so from them per day. And we don’t want to turn off the comments on the blog either.
Thank you.