diff --git a/main.tf b/main.tf
index 819552e..5104968 100644
--- a/main.tf
+++ b/main.tf
@@ -59,7 +59,7 @@ resource "aws_rds_cluster_instance" "writer" {
 
 
 resource "aws_rds_cluster_instance" "reader" {
-  count               = var.reader_instance_type ? 0 : 1
+  count               = var.reader_instance_type == null ? 0 : 1
   cluster_identifier  = aws_rds_cluster.default.cluster_identifier
   identifier          = "${var.identifier}-reader"
   instance_class      = var.reader_instance_type
diff --git a/secret.tf b/secret.tf
index a059798..b6c0774 100644
--- a/secret.tf
+++ b/secret.tf
@@ -16,7 +16,7 @@ locals {
     DB_HOST        = aws_rds_cluster.default.endpoint
     DB_READER_HOST = local.reader_instance_endpoint
   }
-  reader_instance_endpoint = var.reader_instance_type ? "" : aws_rds_cluster_instance.reader[0].endpoint
+  reader_instance_endpoint = var.reader_instance_type == null ? "" : aws_rds_cluster_instance.reader[0].endpoint
   password = random_password.password.result
 }