Spam Checks

==== Required information ====
- iRedMail version (check /etc/iredmail-release): 2.1.3
- Linux/BSD distribution name and version: CentOS7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): SQL
- Web server (Apache or Nginx):  Apache
- Manage mail accounts with iRedAdmin-Pro?  Yes
- Related log if you're reporting an issue: none
====

Thank you for the help.  I have been having issues with receiving over 300 spam emails per day on some of my accounts.  Can you give me a some ideas of where to look to get these spam emails turned away?  I recently turned off the IPV6 for clue bringer, but I don't think that's the core of the problem.  Thoughts?