diff --git a/victoria-metrics/alertmanager.yaml b/victoria-metrics/alertmanager.yaml
index 3485d94..7c681df 100644
--- a/victoria-metrics/alertmanager.yaml
+++ b/victoria-metrics/alertmanager.yaml
@@ -83,4 +83,4 @@ spec:
       - ReadWriteOnce
       resources:
         requests:
-          storage: 4G
+          storage: 500M
diff --git a/victoria-metrics/kustomization.yaml b/victoria-metrics/kustomization.yaml
index 6d52acc..3ca970e 100644
--- a/victoria-metrics/kustomization.yaml
+++ b/victoria-metrics/kustomization.yaml
@@ -216,6 +216,16 @@ patches:
             - --cluster.peer=alertmanager-0.alertmanager:9094
             - --cluster.peer=alertmanager-1.alertmanager:9094
 
+- patch: |
+    - op: add
+      path: /spec/volumeClaimTemplates/0/spec/storageClassName
+      value: synology-iscsi
+  target:
+    group: apps
+    version: v1
+    kind: StatefulSet
+    name: alertmanager
+
 - patch: |
     - op: add
       path: /spec/volumeClaimTemplates/0/spec/storageClassName