diff --git a/src/Pool/AbstractPool.php b/src/Pool/AbstractPool.php
index 9b9f5bc..7ff0bb0 100644
--- a/src/Pool/AbstractPool.php
+++ b/src/Pool/AbstractPool.php
@@ -148,7 +148,7 @@ public function gcObject(int $idleTime)
         }
     }
 
-    public function intervalCheck()
+    protected function intervalCheck()
     {
         $this->gcObject($this->idleGCTime);
     }