This tutorial will show you how to manage ranks in phpBB
From here you can add ranks that will then automatically be given to people as they reach the specified post milestones
5) This will not be a special rank, so select No
6) Enter the number of posts that must be reached before the user achieves this rank
7) Then click Submit
That’s it! The new rank has been added as can be seen here
To delete a rank, you would click the delete icon here
To edit an existing rank, click the edit icon here
This is the end of the tutorial. You now know how to manage ranks in phpBB