Deleting a rule eliminates it permanently – there is no undo or retrieval for a deleted rule. Because of that, be sure you actually want to delete the rule. Deletion of the rules that are pre-configured in the console is not recommended.
You can delete a rule from the Custom rule table by clicking the Delete icon next to the rule you want to delete, and click OK on the configuration dialog.
You can also delete a rule on the Edit Custom Rule page by clicking the View Details icon for the rule in the Custom rules table, and selecting Remove Rule at the bottom of the page.