diff --git a/terraform/monitoring/panels/docdb/available_memory.libsonnet b/terraform/monitoring/panels/docdb/available_memory.libsonnet
index 3e3df16..5981723 100644
--- a/terraform/monitoring/panels/docdb/available_memory.libsonnet
+++ b/terraform/monitoring/panels/docdb/available_memory.libsonnet
@@ -6,7 +6,7 @@ local targets         = grafana.targets;
 local alert           = grafana.alert;
 local alertCondition  = grafana.alertCondition;
 
-local mem_threshold = 4000000000;   // 4GiB
+local mem_threshold = 1500000000;   // 1.5GiB
 local max_memory    = 16000000000;  // 16GiB (AWS DocDB max on db.r6g.large)
 
 local _configuration = defaults.configuration.timeseries