Index: sources/gui/qml/pages/pretreatment/PreTreatmentStack.qml
===================================================================
diff -u -r8457901952a1d732c4688da471ae98e1d4f3024f -reb3bbd3e203463dc3634ecb009b8a1390bb87012
--- sources/gui/qml/pages/pretreatment/PreTreatmentStack.qml	(.../PreTreatmentStack.qml)	(revision 8457901952a1d732c4688da471ae98e1d4f3024f)
+++ sources/gui/qml/pages/pretreatment/PreTreatmentStack.qml	(.../PreTreatmentStack.qml)	(revision eb3bbd3e203463dc3634ecb009b8a1390bb87012)
@@ -28,7 +28,7 @@
  * \brief   the pre treatment stack screen
  */
 StackItem { id: _root
-    stackView.initialItem   : vSettings.advancedMode ? _pretreatmentInstallationAdv : _pretreatmentConcentrates
+    stackView.initialItem   :  null
     enum Step {             // All pretreatment steps advanced and standard
         Concentrates    ,
         Installation    ,
@@ -264,6 +264,12 @@
         }
     }
 
+    Connections { target: vTDOpMode
+        function onPreTreatmentChanged( vValue ) {  if ( vSettings.advancedMode )   { page ( _pretreatmentInstallationAdv   , vValue    )}
+                                                    else                            { page ( _pretreatmentConcentrates      , vValue    )}
+        }
+    }
+
     // TODO in pre treatment story
 //    Connections { target: vPreTreatmentStates
 //        function onWaterSampleChanged           ( vValue ) { page( _preTreatmentWaterSampleStack , vValue )}