diff --git a/Dockerfile b/Dockerfile
index 7513ecc..4e1a867 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -11,6 +11,7 @@ ENV POSTGRES_HOST **None**
 ENV POSTGRES_PORT 5432
 ENV POSTGRES_USER **None**
 ENV POSTGRES_PASSWORD **None**
+ENV POSTGRES_PASSWORD_FILE **None**
 ENV POSTGRES_EXTRA_OPTS '-Z9'
 ENV SCHEDULE '@daily'
 ENV BACKUP_DIR '/backups'