Index: firmware/App/Services/Reservoirs.c
===================================================================
diff -u -r25466a692dfcc7c43413940268f69583614513c3 -r8ceb25eb60c36ccd2d6ff305cb389c5128d6317a
--- firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 25466a692dfcc7c43413940268f69583614513c3)
+++ firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 8ceb25eb60c36ccd2d6ff305cb389c5128d6317a)
@@ -155,8 +155,9 @@
     ratios.bicarbMixingRatio    = 0.0F;
     ratios.timeFillPrepMS       = 0;
 
-    // set the previous target fill volume array
-    memset( prevTargetFillVolumeML, 0x0, NUM_OF_DG_RESERVOIRS );
+    // Initialize the previous reservoir fill volume
+    prevTargetFillVolumeML[ DG_RESERVOIR_1 ] = FILL_RESERVOIR_TO_VOLUME_ML;
+    prevTargetFillVolumeML[ DG_RESERVOIR_2 ] = FILL_RESERVOIR_TO_VOLUME_ML;
 }
 
 /*********************************************************************//**
@@ -528,12 +529,12 @@
     // 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)getTargetFillVolumeBasedOnDialysateFlowML();
+    dilutionLevelPct = volSpentUFML / (F32)prevTargetFillVolumeML[ getDGActiveReservoir() ];
 
     // 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)getTargetFillVolumeBasedOnDialysateFlowML() ) )
+    if ( ( dilutionLevelPct >= MAX_RESERVOIR_DILUTION ) || ( volSpentML >= (F32)prevTargetFillVolumeML[ getDGActiveReservoir() ] ) )
     {
         if ( DG_GEN_IDLE_MODE_STATE_FLUSH_WATER == dgSubMode )
         {