diff --git a/src/auditlog_tests/router.py b/src/auditlog_tests/router.py
index d5a21ae..e4aec3a 100644
--- a/src/auditlog_tests/router.py
+++ b/src/auditlog_tests/router.py
@@ -33,6 +33,6 @@ class PostgresRouter(object):
         Make sure the postgres app only appears in the 'postgres db'
         database.
         """
-        if model_name.startswith('postgres'):
+        if model_name and model_name.startswith('postgres'):
             return db == 'postgres'
         return None
diff --git a/src/auditlog_tests/tests.py b/src/auditlog_tests/tests.py
index fb1a6e3..26b8dde 100644
--- a/src/auditlog_tests/tests.py
+++ b/src/auditlog_tests/tests.py
@@ -575,6 +575,7 @@ class CharfieldTextfieldModelTest(TestCase):
 
 
 class PostgresArrayFieldModelTest(TestCase):
+    databases = '__all__'
 
     def setUp(self):
         self.obj = PostgresArrayFieldModel.objects.create(