diff --git a/clusters/cl01tl/helm/kube-prometheus-stack/values.yaml b/clusters/cl01tl/helm/kube-prometheus-stack/values.yaml
index 20d55f720..cdb335750 100644
--- a/clusters/cl01tl/helm/kube-prometheus-stack/values.yaml
+++ b/clusters/cl01tl/helm/kube-prometheus-stack/values.yaml
@@ -99,7 +99,7 @@ kube-prometheus-stack:
     prometheusSpec:
       scrapeInterval: 30s
       retention: 45d
-      retentionSize: 240Gi
+      retentionSize: 240GiB
       externalUrl: https://prometheus.alexlebens.net
       ruleSelectorNilUsesHelmValues: false
       serviceMonitorSelectorNilUsesHelmValues: false