diff --git a/manifests/tpk8s-opinionated.tanzu.japan.com/10.0.0/hacks/reduce-kafka-replica.yaml b/manifests/tpk8s-opinionated.tanzu.japan.com/10.0.0/hacks/reduce-kafka-replica.yaml
index 1a494af..7cdcec7 100644
--- a/manifests/tpk8s-opinionated.tanzu.japan.com/10.0.0/hacks/reduce-kafka-replica.yaml
+++ b/manifests/tpk8s-opinionated.tanzu.japan.com/10.0.0/hacks/reduce-kafka-replica.yaml
@@ -16,6 +16,7 @@ stringData:
     replicas: 1
     replicationFactor: 1
     insyncReplicas: 1
+    clusterSize: 1
     #@ end
     
     #@overlay/match by=overlay.subset({"kind":"Secret", "metadata": {"name": "ops-kafka-values"}})