diff --git a/templates/postgres-statefulset.yaml b/templates/postgres-statefulset.yaml
index 52a5111..4a1ae7c 100644
--- a/templates/postgres-statefulset.yaml
+++ b/templates/postgres-statefulset.yaml
@@ -66,4 +66,4 @@ spec:
         accessModes: [ReadWriteOnce]
         resources:
           requests:
-            storage: {{ .Values.postgres.storage | quote }}
+            storage: {{ include "instance.storage" (dict "Values" .Values "layer" "database") | quote }}