Of course is hard to pass from filters, but still is a mess who I clean up daily. So I decide to close comments for post older then 21 days. In this way I hope spam bots will reduce activity and have a more clean database.
Akismet put them in spam folder, so no chance to appear live on blog, but still there are a lot of entries in database and a consuming resources of servers even I delete frequently.
How to set up this option?
Go to Settings -> Discussion and search for option “Automatically close comments on posts older than ___ days“. Check that box and put how many days after you publish a post you want for comments to be closed. Default is 14 days, and is a good suggestion but I prefer to leave more days for my readers do post a comment and interact witch other.