Get rid of excess DNS clutter in DNS zone of main domain

Hi there,

I've been looking around / reading up on ways of trying to fix the following issue:

When I edit the DNS zone of my main domain I find all these records of domains that are no longer in use. And with a lot, I mean A LOT. Next to that there are also a lot duplicate A records of domains I'm still using.

As I'm currently entering a new phase of my webproject, I think it's time to clean this up. I've been deleted entries all day - but like this I can go on for another few days and not even be done.

So I was wondering; is there a way to have the DNS zone rebuild from only those domains that are still currently active / added as addon domain on my server? Or is there some way to have the excess clutter removed? I've seen scripts mentioned and other possible ways to get something similar done - but nothing conclusive.

I've actually just passed the fear of doing something wrong in my WHM panel - so I would definitely call myself a newbie in this. I could leave it all be; but then it's just going to get messier and messier over time.

Any suggestions would be more than welcome.

Thanks in advance,