need to remove a RAID1, can't erase from system

I have several RAID1 mirrored drives, holding over from past things I was doing. I need to remove one of them as I upgrade the hard drives.

the device is /dev/md7. Right now it is a degraded array, running on only one partition. I want to remove it so that I can replace the entire disk which holds that partition with a new one, and I will no longer need that RAID volume.

So I ran these commands:

mdadm --stop /dev/md7  
mdadm --remove /dev/md7

Then I went into /etc/mdadm.conf and commented out the line that references md7.
Then I ran mkinitrd again.

Then I rebooted to make sure that md7 didn’t come up again on reboot, and unfortunately it is still there.

What am I doing wrong?

Well, I didn’t really fix it, but I ended up replacing both drives, so it is no longer an issue.