You can implement RBLs to fight spam too. Also like Stephen mentioned, 
if you don't already have SPF, DKIM and DMARC setup, this video may help 
you set them up:

https://www.youtube.com/watch?v=3Pld4ZQf9s4

Amit K Nepal
(OSCP, CISM, CISSP, RHCE, CCENT, C|EH, C|HFI, GIAC ISO 27000 Specialist)

On 6/14/2019 12:04 PM, Stephen Partington wrote:
> Do you have DKIM and DMARC records as well?
>
> On Fri, Jun 14, 2019 at 11:26 AM <kitepilot@kitepilot.com 
> <mailto:kitepilot@kitepilot.com>> wrote:
>
>     Hello all:
>     I run my own DNS and email servers.
>     I have the SPF records properly set but I am having a crippling
>     amount of
>     email spoofing by spammers, how can I prevent that?   :(
>     Thanks
>     ET
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> -- 
> A mouse trap, placed on top of your alarm clock, will prevent you from 
> rolling over and going back to sleep after you hit the snooze button.
>
> Stephen
>
>
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