diff --git a/tests/fixture/tmpnet/defaults.go b/tests/fixture/tmpnet/defaults.go
index fc42841f8a2d..33d9ab449c02 100644
--- a/tests/fixture/tmpnet/defaults.go
+++ b/tests/fixture/tmpnet/defaults.go
@@ -33,7 +33,7 @@ const (
 	DefaultMinStakeDuration = time.Second
 
 	// Reducing this from the 1s default speeds up tx acceptance
-	DefaultProposerMinBlockDelay = 0 * time.Second
+	DefaultProposerMinBlockDelay = "0s"
 
 	defaultConfigFilename = "config.json"
 )