diff --git a/module/VuFind/src/VuFind/Controller/Plugin/Holds.php b/module/VuFind/src/VuFind/Controller/Plugin/Holds.php
index 1b6e3f31353430611d86351b07d0b10eeff714d0..3e95b87b9ce76f8defabac4931fa5efb3e86dd60 100644
--- a/module/VuFind/src/VuFind/Controller/Plugin/Holds.php
+++ b/module/VuFind/src/VuFind/Controller/Plugin/Holds.php
@@ -212,7 +212,7 @@ class Holds extends AbstractPlugin
         $gatheredDetails['id'] = $params->fromRoute('id');
 
         // Get Values Passed from holdings.php
-        $gatheredDetails += $keyValueArray;
+        $gatheredDetails = array_merge($gatheredDetails, $keyValueArray);
 
         return $gatheredDetails;
     }