XF 2.2 Prevent registrations of 'Stopforumspam' IPs?

Hello there. Recently I've had a few alerts on my forum about users that need approval, which I find that their IPs are on the list of 'stopforumspam'. I have to manually reject their registration, and ban their user account. Is there an easier way to do this? Or even better, just block them from registration at all? I aint sure why they are even allowed to register, if their IPs match 'stopforumspam'? Is there something I can do in ACP to just block their registration in the first place? I dont even want them to waste a user ID from my database.
I see, so change this value from 3 to 1, it will reject registration for any IPs that exist in stopforumspam database? Thanks, I've just done that and hopefully the spambots wont even sign up anymore.