Blocking some FTP sites
I'm new to pfSense (although not quite new to pf). I apologize for such a basic question, but how can I block access to some specific FTP sites from my LAN? I have the ftp helper enabled and this rdr's all ftp traffic to the ftp proxy, so any 'block' firewall rules that I create for e.g. destination host 188.8.131.52 port 21 have no effect. I see no way in the web GUI to specify that traffic to some specific ftp host not be rdr'd to the ftp proxy. I'm probably overlooking something obvious, but what?
For now I just entered fake IP addresses for these addresses in the DNS forwarder configuration, but this of course means that clients can still connect using IP address.