diff --git a/whisper/whisperv6/api.go b/whisper/whisperv6/api.go
index 3dddb69539..f6158b641c 100644
--- a/whisper/whisperv6/api.go
+++ b/whisper/whisperv6/api.go
@@ -118,7 +118,7 @@ func (api *PublicWhisperAPI) SetMaxMessageSize(ctx context.Context, size uint32)
 
 // SetMinPow sets the minimum PoW for a message before it is accepted.
 func (api *PublicWhisperAPI) SetMinPoW(ctx context.Context, pow float64) (bool, error) {
-	return true, api.w.SetMinimumPoW(pow)
+	return true, api.w.SetMinimumPoW(pow, false)
 }
 
 // MarkTrustedPeer marks a peer trusted. , which will allow it to send historic (expired) messages.
diff --git a/whisper/whisperv6/peer_test.go b/whisper/whisperv6/peer_test.go
index 39a4ab1980..d1c217da95 100644
--- a/whisper/whisperv6/peer_test.go
+++ b/whisper/whisperv6/peer_test.go
@@ -114,7 +114,7 @@ func initialize(t *testing.T) {
 	for i := 0; i < NumNodes; i++ {
 		var node TestNode
 		node.shh = New(&DefaultConfig)
-		node.shh.SetMinimumPoW(0.00000001)
+		node.shh.SetMinimumPoW(0.00000001, true)
 		node.shh.Start(nil)
 		topics := make([]TopicType, 0)
 		topics = append(topics, sharedTopic)
diff --git a/whisper/whisperv6/whisper.go b/whisper/whisperv6/whisper.go
index f52ee6e9ee..ad1897e802 100644
--- a/whisper/whisperv6/whisper.go
+++ b/whisper/whisperv6/whisper.go
@@ -181,17 +181,22 @@ func (w *Whisper) SetMaxMessageSize(size uint32) error {
 }
 
 // SetMinimumPoW sets the minimal PoW required by this node
-func (w *Whisper) SetMinimumPoW(val float64) error {
+func (w *Whisper) SetMinimumPoW(val float64, testMode bool) error {
 	if val <= 0.0 {
 		return fmt.Errorf("invalid PoW: %f", val)
 	}
+
 	w.notifyPeersAboutPowRequirementChange(val)
 
-	go func() {
-		// allow some time before all the peers have processed the notification
-		time.Sleep(time.Duration(w.reactionAllowance) * time.Second)
+	if testMode {
 		w.settings.Store(minPowIdx, val)
-	}()
+	} else {
+		go func() {
+			//	// allow some time before all the peers have processed the notification
+			time.Sleep(time.Duration(w.reactionAllowance) * time.Second)
+			w.settings.Store(minPowIdx, val)
+		}()
+	}
 
 	return nil
 }
diff --git a/whisper/whisperv6/whisper_test.go b/whisper/whisperv6/whisper_test.go
index c8f3a9ed74..009f50d3cb 100644
--- a/whisper/whisperv6/whisper_test.go
+++ b/whisper/whisperv6/whisper_test.go
@@ -472,8 +472,8 @@ func TestExpiry(t *testing.T) {
 	InitSingleTest()
 
 	w := New(&DefaultConfig)
-	w.SetMinimumPoW(0.0000001)
-	defer w.SetMinimumPoW(DefaultMinimumPoW)
+	w.SetMinimumPoW(0.0000001, true)
+	defer w.SetMinimumPoW(DefaultMinimumPoW, true)
 	w.Start(nil)
 	defer w.Stop()
 
@@ -529,7 +529,7 @@ func TestCustomization(t *testing.T) {
 	InitSingleTest()
 
 	w := New(&DefaultConfig)
-	defer w.SetMinimumPoW(DefaultMinimumPoW)
+	defer w.SetMinimumPoW(DefaultMinimumPoW, true)
 	defer w.SetMaxMessageSize(DefaultMaxMessageSize)
 	w.Start(nil)
 	defer w.Stop()
@@ -563,7 +563,7 @@ func TestCustomization(t *testing.T) {
 		t.Fatalf("successfully sent envelope with PoW %.06f, false positive (seed %d).", env.PoW(), seed)
 	}
 
-	w.SetMinimumPoW(smallPoW / 2)
+	w.SetMinimumPoW(smallPoW/2, true)
 	err = w.Send(env)
 	if err != nil {
 		t.Fatalf("failed to send envelope with seed %d: %s.", seed, err)
@@ -625,7 +625,7 @@ func TestSymmetricSendCycle(t *testing.T) {
 	InitSingleTest()
 
 	w := New(&DefaultConfig)
-	defer w.SetMinimumPoW(DefaultMinimumPoW)
+	defer w.SetMinimumPoW(DefaultMinimumPoW, true)
 	defer w.SetMaxMessageSize(DefaultMaxMessageSize)
 	w.Start(nil)
 	defer w.Stop()
@@ -714,7 +714,7 @@ func TestSymmetricSendWithoutAKey(t *testing.T) {
 	InitSingleTest()
 
 	w := New(&DefaultConfig)
-	defer w.SetMinimumPoW(DefaultMinimumPoW)
+	defer w.SetMinimumPoW(DefaultMinimumPoW, true)
 	defer w.SetMaxMessageSize(DefaultMaxMessageSize)
 	w.Start(nil)
 	defer w.Stop()
@@ -782,7 +782,7 @@ func TestSymmetricSendKeyMismatch(t *testing.T) {
 	InitSingleTest()
 
 	w := New(&DefaultConfig)
-	defer w.SetMinimumPoW(DefaultMinimumPoW)
+	defer w.SetMinimumPoW(DefaultMinimumPoW, true)
 	defer w.SetMaxMessageSize(DefaultMaxMessageSize)
 	w.Start(nil)
 	defer w.Stop()