diff --git a/docs/apps/petio.md b/docs/apps/petio.md
index 6c3863fbc..a2e5e53fa 100644
--- a/docs/apps/petio.md
+++ b/docs/apps/petio.md
@@ -30,7 +30,7 @@ sb install petio
 
 - After setting up your credentials, you need to pick your Plex server.
 
-- Leave MongoDB settings as default.
+- MongoDB: Use petio-mongo:27017 (assumes default petio_name otherwise it is the value of petio_name plus -mongo)
 
 - Once the last step is finished, you will be presented with a login screen. Use your Plex username and the password you set up on Step 2. You can now get started with configuring Radarr, Sonarr and start requesting!