diff --git a/src/core_ocean/Registry.xml b/src/core_ocean/Registry.xml
index afdd15b45d..7138d9cb58 100644
--- a/src/core_ocean/Registry.xml
+++ b/src/core_ocean/Registry.xml
@@ -2031,6 +2031,7 @@
 	<var_struct name="state" time_levs="2">
 		<var name="normalVelocity" type="real" dimensions="nVertLevels nEdges Time" units="m s^{-1}"
 			 description="horizonal velocity, normal component to an edge"
+       missing_value="FILLVAL"
 		/>
 		<var name="layerThickness" type="real" dimensions="nVertLevels nCells Time" units="m"
 			 description="layer thickness"
diff --git a/src/core_ocean/tracer_groups/Registry_activeTracers.xml b/src/core_ocean/tracer_groups/Registry_activeTracers.xml
index 66e2dba813..dd57ea9ec5 100644
--- a/src/core_ocean/tracer_groups/Registry_activeTracers.xml
+++ b/src/core_ocean/tracer_groups/Registry_activeTracers.xml
@@ -61,7 +61,7 @@
 
 	<var_struct name="state" time_levs="2">
 		<var_struct name="tracers" time_levs="2">
-			<var_array name="activeTracers" dimensions="nVertLevels nCells Time" type="real" packages="activeTracersPKG" >
+			<var_array name="activeTracers" dimensions="nVertLevels nCells Time" type="real" packages="activeTracersPKG" missing_value="FILLVAL">
 				<var name="temperature" array_group="activeGRP" units="degrees Celsius"
 			 description="potential temperature"
 				/>
diff --git a/src/tools/registry/gen_inc.c b/src/tools/registry/gen_inc.c
index 965efed6c5..b752f6c98a 100644
--- a/src/tools/registry/gen_inc.c
+++ b/src/tools/registry/gen_inc.c
@@ -1386,10 +1386,10 @@ int parse_var_array(FILE *fd, ezxml_t registry, ezxml_t superStruct, ezxml_t var
 				fortprintf(fd, "         call mpas_add_att(%s(%d) %% attLists(const_index) %% attList, 'units', '%s')\n", pointer_name, time_lev, temp_str);
 			}
 
-			if ( vararrmissingval ) {
-				fortprintf(fd, "         call mpas_add_att(%s(%d) %% attLists(const_index) %% attList, 'missing_value', %s)\n", pointer_name, time_lev, missing_value);
+			if ( vararrmissingval != NULL ) {
+				// fortprintf(fd, "         call mpas_add_att(%s(%d) %% attLists(const_index) %% attList, 'missing_value', %s)\n", pointer_name, time_lev, missing_value);
 				// Uncomment to add _FillValue to match missing_value
-				// fortprintf(fd, "         call mpas_add_att(%s(%d) %% attLists(const_index) %% attList, '_FillValue', %s)\n", pointer_name, time_lev, missing_value);
+				fortprintf(fd, "         call mpas_add_att(%s(%d) %% attLists(const_index) %% attList, '_FillValue', %s)\n", pointer_name, time_lev, missing_value);
 			}
 			fortprintf(fd, "         %s(%d) %% missingValue = %s\n", pointer_name, time_lev, missing_value);
 			fortprintf(fd, "         %s(%d) %% constituentNames(const_index) = '%s'\n", pointer_name, time_lev, varname);
@@ -1431,7 +1431,6 @@ int parse_var_array(FILE *fd, ezxml_t registry, ezxml_t superStruct, ezxml_t var
 	return 0;
 }/*}}}*/
 
-
 int parse_var(FILE *fd, ezxml_t registry, ezxml_t superStruct, ezxml_t currentVar, const char * corename)/*{{{*/
 {
 	ezxml_t struct_xml, var_xml, var_xml2;
@@ -1596,9 +1595,9 @@ int parse_var(FILE *fd, ezxml_t registry, ezxml_t superStruct, ezxml_t currentVa
 		}
 
 		if ( varmissingval != NULL ) {
-			fortprintf(fd, "      call mpas_add_att(%s(%d) %% attLists(1) %% attList, 'missing_value', %s)\n", pointer_name, time_lev, missing_value);
+			// fortprintf(fd, "      call mpas_add_att(%s(%d) %% attLists(1) %% attList, 'missing_value', %s)\n", pointer_name, time_lev, missing_value);
 			// Uncomment to add _FillValue to match missing_value
-			// fortprintf(fd, "      call mpas_add_att(%s(%d) %% attLists(1) %% attList, '_FillValue', %s)\n", pointer_name, time_lev, missing_value);
+			fortprintf(fd, "      call mpas_add_att(%s(%d) %% attLists(1) %% attList, '_FillValue', %s)\n", pointer_name, time_lev, missing_value);
 		}
 		fortprintf(fd, "      %s(%d) %% missingValue = %s\n", pointer_name, time_lev, missing_value);
 
@@ -1672,7 +1671,7 @@ int parse_struct(FILE *fd, ezxml_t registry, ezxml_t superStruct, int subpool, c
 
 	structname = ezxml_attr(superStruct, "name");
 	structnameincode = ezxml_attr(superStruct, "name_in_code");
-	
+
 	if(!structnameincode){
 		structnameincode = ezxml_attr(superStruct, "name");
 	}
@@ -2123,7 +2122,7 @@ int generate_immutable_streams(ezxml_t registry){/*{{{*/
 											fortprintf(fd, "   call MPAS_stream_mgr_add_field(manager, \'%s\', \'%s\', packages=packages, ierr=ierr)\n", optname, optvarname);
 										else
 											fortprintf(fd, "   call MPAS_stream_mgr_add_field(manager, \'%s\', \'%s\', ierr=ierr)\n", optname, optvarname);
-										
+
 									}
 
 									/* Loop over arrays of fields listed within the stream */
@@ -2571,5 +2570,3 @@ int parse_structs_from_registry(ezxml_t registry)/*{{{*/
 
 	return 0;
 }/*}}}*/
-
-