Index: firmware/App/Controllers/DGInterface.c
===================================================================
diff -u -r27f3db92495948d4c1192421c1b0c20338c4a034 -re8f30ca933a7c373c1a4a749ad84adb2f63b7722
--- firmware/App/Controllers/DGInterface.c	(.../DGInterface.c)	(revision 27f3db92495948d4c1192421c1b0c20338c4a034)
+++ firmware/App/Controllers/DGInterface.c	(.../DGInterface.c)	(revision e8f30ca933a7c373c1a4a749ad84adb2f63b7722)
@@ -57,7 +57,8 @@
 
 // DG status
 static DG_OP_MODE_T dgCurrentOpMode = DG_MODE_INIT;             ///< Current DG operation mode.
-static U32 dgSubMode = 0;                                       ///< Current state (sub-mode) of current DG operation mode.
+static U32 dgSubMode = 0;                                       ///< Current state (sub-mode) of current DG operation mode.
+static BOOL dgStartCommandSent = FALSE;                         ///< Flag indicates command to start DG has been sent.
 static BOOL dgStarted = FALSE;                                  ///< Flag indicates whether we have commanded the DG to start or stop.
 static BOOL dgTrimmerHeaterOn = FALSE;                          ///< Flag indicates whether we have commanded the DG to start or stop the trimmer heater.
 static BOOL dgWaterSampled = FALSE;                             ///< Flag indicates whether we have commanded the DG to sample water.
@@ -734,7 +735,7 @@
  *************************************************************************/
 void cmdStartDG( void )
 {
-    dgStarted = TRUE;
+    dgStartCommandSent = TRUE;
     sendDGStartStopCommand( START_DG_CMD );
 }
 
@@ -839,8 +840,22 @@
 {
     dgCmdResp[ DG_CMD_START_FILL ].commandID = DG_CMD_NONE;
     dgReservoirFillVolumeTargetSet = fillToVolMl;
-    sendDGFillCommand( fillToVolMl );
+    sendDGFillCommand( DG_CMD_START, fillToVolMl );
 }
+
+/*********************************************************************//**
+ * @brief
+ * The cmdStopDGFill function sends a fill command with stop parameter message to the DG.
+ * @details Inputs: none
+ * @details Outputs: fill command with stop parameter sent to DG.
+ * @return none
+ *************************************************************************/
+void cmdStopDGFill( void )
+{
+    dgCmdResp[ DG_CMD_STOP_FILL ].commandID = DG_CMD_NONE;
+    dgReservoirFillVolumeTargetSet = 0;
+    sendDGFillCommand( DG_CMD_STOP, 0 );
+}
 
 /*********************************************************************//**
  * @brief
Index: firmware/App/Controllers/DGInterface.h
===================================================================
diff -u -r27f3db92495948d4c1192421c1b0c20338c4a034 -re8f30ca933a7c373c1a4a749ad84adb2f63b7722
--- firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision 27f3db92495948d4c1192421c1b0c20338c4a034)
+++ firmware/App/Controllers/DGInterface.h	(.../DGInterface.h)	(revision e8f30ca933a7c373c1a4a749ad84adb2f63b7722)
@@ -32,7 +32,7 @@
 
 // ********** public definitions **********
 
-#define DRAIN_RESERVOIR_TO_VOLUME_ML        200     ///< Drain reservoir to this volume (in mL) during treatment.
+#define DRAIN_RESERVOIR_TO_VOLUME_ML        0       ///< Drain reservoir to this volume (in mL) during treatment.
 #ifndef V1_5_SYSTEM
 #define FILL_RESERVOIR_TO_VOLUME_ML         1700    ///< Fill reservoir to this volume (in mL) during treatment.
 #else
@@ -149,7 +149,8 @@
 void cmdStopDG( void );
 void cmdSetDGActiveReservoir( DG_RESERVOIR_ID_T resID );
 void cmdChangeDGValveSetting( DG_VALVE_SETTING_ID_T valveSettingID );
-void cmdStartDGFill( U32 fillToVolMl );
+void cmdStartDGFill( U32 fillToVolMl );
+void cmdStopDGFill( void );
 void cmdStartDGDrain( U32 drainToVolMl, BOOL tareLoadCell );
 void cmdStartDGTrimmerHeater( void );
 void cmdStopDGTrimmerHeater( void );
Index: firmware/App/Modes/ModePostTreat.c
===================================================================
diff -u -r2346a0cb59957d90fe61cb3bff4ec7ffc3df10a4 -re8f30ca933a7c373c1a4a749ad84adb2f63b7722
--- firmware/App/Modes/ModePostTreat.c	(.../ModePostTreat.c)	(revision 2346a0cb59957d90fe61cb3bff4ec7ffc3df10a4)
+++ firmware/App/Modes/ModePostTreat.c	(.../ModePostTreat.c)	(revision e8f30ca933a7c373c1a4a749ad84adb2f63b7722)
@@ -107,8 +107,8 @@
 {
     initPostTreatmentMode();
 
-    // TODO - stop any DG fill that may be in progress from an aborted treatment
-    // cmdStopDGFill();
+    // Stop any DG fill that may be in progress from an aborted treatment
+    cmdStopDGFill();
 
     // Set user alarm recovery actions allowed in this mode
     setAlarmUserActionEnabled( ALARM_USER_ACTION_RESUME, TRUE );
Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r2346a0cb59957d90fe61cb3bff4ec7ffc3df10a4 -re8f30ca933a7c373c1a4a749ad84adb2f63b7722
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 2346a0cb59957d90fe61cb3bff4ec7ffc3df10a4)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision e8f30ca933a7c373c1a4a749ad84adb2f63b7722)
@@ -666,11 +666,12 @@
  * The sendDGFillCommand function constructs a DG fill command message
  * and queues the msg for transmit on the appropriate CAN channel.
  * @details Inputs: none
- * @details Outputs: DG fill command msg constructed and queued.
+ * @details Outputs: DG fill command msg constructed and queued.
+ * @param cmd start or stop fill command
  * @param fillToVolumeMl volume (in mL) to fill inactive reservoir to
  * @return TRUE if msg successfully queued for transmit, FALSE if not
  *************************************************************************/
-BOOL sendDGFillCommand( U32 fillToVolumeMl )
+BOOL sendDGFillCommand( U32 cmd, U32 fillToVolumeMl )
 {
     BOOL result;
     MESSAGE_T msg;
@@ -679,10 +680,12 @@
     // Create a message record
     blankMessage( &msg );
     msg.hdr.msgID = MSG_ID_DG_FILL_CMD;
-    msg.hdr.payloadLen = sizeof( U32 );
+    msg.hdr.payloadLen = sizeof( U32 ) + sizeof( U32 );
+
+    memcpy( payloadPtr, &fillToVolumeMl, sizeof( U32 ) );
+    payloadPtr += sizeof( U32 );
+    memcpy( payloadPtr, &cmd, sizeof( U32 ) );
 
-    memcpy( payloadPtr, &fillToVolumeMl, sizeof( U32 ) );
-
     // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
     result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_DG, ACK_REQUIRED );
 
@@ -2629,7 +2632,6 @@
     /*********************************************************************//**
      * @brief
      * The sendDebugDataToUI function sends debug string to the UI for logging.
-     * @details
      * @details Inputs: none
      * @details Outputs: Message constructed and queued for transmit
      * @param str Pointer to debug string
Index: firmware/App/Services/SystemCommMessages.h
===================================================================
diff -u -r2346a0cb59957d90fe61cb3bff4ec7ffc3df10a4 -re8f30ca933a7c373c1a4a749ad84adb2f63b7722
--- firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision 2346a0cb59957d90fe61cb3bff4ec7ffc3df10a4)
+++ firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision e8f30ca933a7c373c1a4a749ad84adb2f63b7722)
@@ -207,7 +207,7 @@
 BOOL sendDGChangeValveSettingCommand( U32 valveSettingCmd );
 
 // MSG_ID_DG_FILL_CMD
-BOOL sendDGFillCommand( U32 fillToVolumeMl );
+BOOL sendDGFillCommand( U32 cmd, U32 fillToVolumeMl );
 
 // MSG_ID_DG_DRAIN_CMD
 BOOL sendDGDrainCommand( DRAIN_RESERVOIR_CMD_PAYLOAD_T *drainCmdPtr );