Index: firmware/App/Services/Reservoirs.c
===================================================================
diff -u -rd611c5eeaee076a6fbf79cf94f80fff05fd5d9a9 -rd33b56765d3eeb3853eb84697d05c8a91441e00f
--- firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision d611c5eeaee076a6fbf79cf94f80fff05fd5d9a9)
+++ firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision d33b56765d3eeb3853eb84697d05c8a91441e00f)
@@ -58,6 +58,7 @@
 #define DIA_FLOW_TO_FILL_FLOW_CONSTANT                    2.0F                                           ///< Dialysate flow rate to fill flow rate constant.
 
 #define MAX_RESERVOIR_VOL_BEFORE_SWITCH_ML                1900.0F                                        ///< Maximum reservoir volume before we switch reservoirs (in mL).
+#define FILL_VOLUME_INTERCEPT_ML_QD_ABOVE_400_MLPM        1100                                           ///< Fill volume intercept in milliliters for Qd above 400 mL/min.
 
 // ********** private data **********
 
@@ -106,6 +107,7 @@
 static F32 getReservoirRecirculationMaxPercent( void );
 static void publishReservoirData( void );
 static BOOL isDialysateTempAlarmActive( void );
+static U32 getTargetFillVolumeBasedOnDialysateFlowML( void );
 
 static TREATMENT_RESERVOIR_MGMT_STATE_T handleReservoirMgmtStartState( void );
 static TREATMENT_RESERVOIR_MGMT_STATE_T handleReservoirMgmtDrainState( void );
@@ -194,7 +196,7 @@
         volSpentML += ( flowRateMLPerMS * msSinceLastVolumeCalc );
         timeReservoirInUse++;
         // Check the recirculation level
-        recirculationLevelPct = volSpentML / (F32)FILL_RESERVOIR_TO_VOLUME_ML;
+        recirculationLevelPct = volSpentML / (F32)getTargetFillVolumeBasedOnDialysateFlowML();
     }
 
     // Update the reservoir start time
@@ -314,7 +316,7 @@
     F32 totalTargetFillFlow   = targetFillFlowRate + ( targetFillFlowRate * ratios.acidMixingRatio ) +
                                                      ( targetFillFlowRate * ratios.bicarbMixingRatio );
     // Time fill = Fill volume / Qfill. Qfill is converted from L/min to mL/min and the time is converted from minutes to milliseconds
-    U32 timeFillMS            = ( FILL_RESERVOIR_TO_VOLUME_ML / ( ML_PER_LITER * totalTargetFillFlow ) ) * SEC_PER_MIN * MS_PER_SECOND;
+    U32 timeFillMS            = ( getTargetFillVolumeBasedOnDialysateFlowML() / ( ML_PER_LITER * totalTargetFillFlow ) ) * SEC_PER_MIN * MS_PER_SECOND;
     // Add the prepare time in the DG mode fill to the calculated fill time in milliseconds
     U32 timeTotalFillMS       = timeFillMS + ratios.timeFillPrepMS;
 
@@ -334,21 +336,21 @@
 static void calculateActiveReservoirCycleTime( void )
 {
     U32 dialysateFlowMLP     = getTreatmentParameterU32( TREATMENT_PARAM_DIALYSATE_FLOW );
-    F32 fillTimeMS           = ( (F32)FILL_RESERVOIR_TO_VOLUME_ML / ( getTargetFillFlowRateLPM() * ML_PER_LITER ) ) * SEC_PER_MIN * MS_PER_SECOND;
+    F32 fillTimeMS           = ( (F32)getTargetFillVolumeBasedOnDialysateFlowML() / ( getTargetFillFlowRateLPM() * ML_PER_LITER ) ) * SEC_PER_MIN * MS_PER_SECOND;
     F32 targetUFFlowMLP      = getCurrentUFSetRate();
-    F32 timeDepletionMS      = ( (F32)FILL_RESERVOIR_TO_VOLUME_ML / dialysateFlowMLP ) * SEC_PER_MIN * MS_PER_SECOND;
+    F32 timeDepletionMS      = ( (F32)getTargetFillVolumeBasedOnDialysateFlowML() / dialysateFlowMLP ) * SEC_PER_MIN * MS_PER_SECOND;
     F32 timeTotalCycleMS     = fillTimeMS + RESERVOIR_FRESH_SETTLE_TIME_MS + RESERVOIR_CYCLE_EXTRA_MARGIN_TIME_MS + ratios.timeFillPrepMS;
     F32 timeReservoirCycleMS = 0.0F;
     F32 timeUFDepletionMS    = NEARLY_INFINITY;
-    F32 volFreshML           = FILL_RESERVOIR_TO_VOLUME_ML - volSpentML;
+    F32 volFreshML           = getTargetFillVolumeBasedOnDialysateFlowML() - volSpentML;
     F32 timeFreshRemainingMS = ( volFreshML / (F32)dialysateFlowMLP ) * SEC_PER_MIN * MS_PER_SECOND;
-    F32 volMaxUFML           = FILL_RESERVOIR_TO_VOLUME_ML * MAX_RESERVOIR_DILUTION;
+    F32 volMaxUFML           = getTargetFillVolumeBasedOnDialysateFlowML() * MAX_RESERVOIR_DILUTION;
 
     // Check if target UF flow is not zero to consider it in the calculations too
     if ( targetUFFlowMLP > NEARLY_ZERO )
     {
         // If UF is not 0, the active reservoir cycle time is minimum of UF depletion and fill time
-        timeUFDepletionMS = ( ( (F32)FILL_RESERVOIR_TO_VOLUME_ML * RESERVOIR_DILUTION_RATIO ) / targetUFFlowMLP ) * SEC_PER_MIN * MS_PER_SECOND;
+        timeUFDepletionMS = ( ( (F32)getTargetFillVolumeBasedOnDialysateFlowML() * RESERVOIR_DILUTION_RATIO ) / targetUFFlowMLP ) * SEC_PER_MIN * MS_PER_SECOND;
         // Calculate the ultra-filtration remaining volume
         // Using the ultra-filtration remaining volume and the ultra-filtration target flow rate calculate the time
         // The depletion time in milliseconds is the minimum time of the fresh remaining time and the depletion remaining time
@@ -518,24 +520,24 @@
     // Get the ultra-filtration volume milliliters
     // Get the dilution level in percent = spent ultra-filtration volume / target fill volume in milliliters
     volSpentUFML     = getReservoirUltrafiltrationVol( activeReservoir );
-    dilutionLevelPct = volSpentUFML / (F32)FILL_RESERVOIR_TO_VOLUME_ML;
+    dilutionLevelPct = volSpentUFML / (F32)getTargetFillVolumeBasedOnDialysateFlowML();
 
     // Check if the dilution level has exceeded the limit or the spent volume is more than the amount of volume in the reservoir
     // If it has, trigger the fill command. This if should not happen and the predictive dilution level should trigger just in time
     // in advance
-    if ( ( dilutionLevelPct >= MAX_RESERVOIR_DILUTION ) || ( volSpentML >= (F32)FILL_RESERVOIR_TO_VOLUME_ML ) )
+    if ( ( dilutionLevelPct >= MAX_RESERVOIR_DILUTION ) || ( volSpentML >= (F32)getTargetFillVolumeBasedOnDialysateFlowML() ) )
     {
         if ( DG_GEN_IDLE_MODE_STATE_FLUSH_WATER == dgSubMode )
         {
-            cmdStartDGFill( FILL_RESERVOIR_TO_VOLUME_ML, targetFillFlowRateLPM );
+            cmdStartDGFill( getTargetFillVolumeBasedOnDialysateFlowML(), targetFillFlowRateLPM );
         }
     }
     // If we have active dialysate temp alarms, we want to fill immediately.
     else if ( TRUE == isDialysateTempAlarmActive() )
     {
         if ( DG_GEN_IDLE_MODE_STATE_FLUSH_WATER == dgSubMode )
         {
-            cmdStartDGFill( FILL_RESERVOIR_TO_VOLUME_ML, targetFillFlowRateLPM );
+            cmdStartDGFill( getTargetFillVolumeBasedOnDialysateFlowML(), targetFillFlowRateLPM );
         }
     }
     else
@@ -548,7 +550,7 @@
         // If the wait time has elapsed, trigger a fill command
         if ( timeWaitToFillMS <= 0 )
         {
-            cmdStartDGFill( FILL_RESERVOIR_TO_VOLUME_ML, targetFillFlowRateLPM );
+            cmdStartDGFill( getTargetFillVolumeBasedOnDialysateFlowML(), targetFillFlowRateLPM );
         }
     }
 
@@ -618,11 +620,11 @@
     // Get the ultra-filtration volume milliliters
     // Get the dilution level in percent = spent ultra-filtration volume / target fill volume in milliliters
     volSpentUFML     = getReservoirUltrafiltrationVol( activeReservoir );
-    dilutionLevelPct = volSpentUFML / (F32)FILL_RESERVOIR_TO_VOLUME_ML;
+    dilutionLevelPct = volSpentUFML / (F32)getTargetFillVolumeBasedOnDialysateFlowML();
 
     // Wait for the reservoir to settle and then send the commands to switch the active reservoir
     if ( ( TRUE == didTimeout( reservoirSwitchStartTimeMS, RESERVOIR_FRESH_SETTLE_TIME_MS ) ) &&
-       ( ( dilutionLevelPct >= MAX_RESERVOIR_DILUTION ) || ( volSpentML >= (F32)FILL_RESERVOIR_TO_VOLUME_ML ) || ( TRUE == isDialysateTempAlarmActive() ) ) )
+       ( ( dilutionLevelPct >= MAX_RESERVOIR_DILUTION ) || ( volSpentML >= (F32)getTargetFillVolumeBasedOnDialysateFlowML() ) || ( TRUE == isDialysateTempAlarmActive() ) ) )
     {
         DG_SWITCH_RSRVRS_CMD_T rsrvrCmd;
 
@@ -703,4 +705,25 @@
     return result;
 }
 
+/*********************************************************************//**
+ * @brief
+ * The getTargetFillVolumeBasedOnDialysateFlowML function calculates the
+ * target fill volume in milliliters.
+ * @details Inputs: none
+ * @details Outputs: none
+ * @return Fill target volume in milliliters
+ *************************************************************************/
+static U32 getTargetFillVolumeBasedOnDialysateFlowML( void )
+{
+    U32 targetFillVolumeML = FILL_RESERVOIR_TO_VOLUME_ML;
+    U32 dialysateFlowMLP   = getTreatmentParameterU32( TREATMENT_PARAM_DIALYSATE_FLOW );
+
+    if ( dialysateFlowMLP >= RESERVOIR_FLOW_400_MLP )
+    {
+        targetFillVolumeML = dialysateFlowMLP + FILL_VOLUME_INTERCEPT_ML_QD_ABOVE_400_MLPM;
+    }
+
+    return targetFillVolumeML;
+}
+
 /**@}*/