diff --git a/tests/3_system/test_custom_compset_std_grid.py b/tests/3_system/test_custom_compset_std_grid.py
new file mode 100755
index 0000000..e591546
--- /dev/null
+++ b/tests/3_system/test_custom_compset_std_grid.py
@@ -0,0 +1,107 @@
+#!/usr/bin/env python3
+
+import pytest
+import shutil
+import os
+from pathlib import Path
+import tempfile
+import time
+
+from ProConPy.config_var import ConfigVar, cvars
+from ProConPy.stage import Stage
+from ProConPy.csp_solver import csp
+from visualCaseGen.cime_interface import CIME_interface
+from visualCaseGen.initialize_configvars import initialize_configvars
+from visualCaseGen.initialize_widgets import initialize_widgets
+from visualCaseGen.initialize_stages import initialize_stages
+from visualCaseGen.specs.options import set_options
+from visualCaseGen.specs.relational_constraints import get_relational_constraints
+from visualCaseGen.custom_widget_types.mom6_bathy_launcher import MOM6BathyLauncher
+from visualCaseGen.custom_widget_types.case_creator_widget import CaseCreatorWidget
+from tests.utils import safe_create_case
+
+
+# do not show logger output
+import logging
+
+logger = logging.getLogger()
+logger.setLevel(logging.CRITICAL)
+
+base_temp_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "temp"))
+
+
+def test_custom_compset_std_grid():
+    """Configure a custom compset with a standard grid: 2000_DATM%JRA_SLND_CICE%PRES_MOM6_SROF_SGLC_WW3. Progress through the stages
+    until the launch stage is reached."""
+
+    ConfigVar.reboot()
+    Stage.reboot()
+    cime = CIME_interface()
+    initialize_configvars(cime)
+    initialize_widgets(cime)
+    initialize_stages(cime)
+    set_options(cime)
+    csp.initialize(cvars, get_relational_constraints(cvars), Stage.first())
+
+    # At initialization, the first stage should be enabled
+    assert Stage.first().enabled
+    cvars['COMPSET_MODE'].value = 'Custom'
+
+    # CCOMPSET_MODE is the only variable in the first stage, so assigning a value to it should disable the first stage
+    assert not Stage.first().enabled
+    
+    # The next stge is Custom Component Set, whose first child is Model Time Period
+    assert Stage.active().title.startswith('Time Period')
+    cvars['INITTIME'].value = '1850'
+
+    cvars['COMP_OCN'].value = "mom"
+    cvars['COMP_ICE'].value = "sice"
+    cvars['COMP_ATM'].value = "cam"
+    cvars['COMP_ROF'].value = "mosart"
+    cvars['COMP_LND'].value = "clm"
+    cvars['COMP_WAV'].value = "swav"
+    cvars['COMP_GLC'].value = "sglc"
+
+
+    assert Stage.active().title.startswith('Component Physics')
+
+    cvars['COMP_ATM_PHYS'].value = "CAM60"
+    cvars['COMP_LND_PHYS'].value = "CLM60"
+
+    assert Stage.active().title.startswith('Component Options')
+
+    cvars['COMP_ATM_OPTION'].value = "1PCT"
+    cvars['COMP_LND_OPTION'].value = "BGC"
+    cvars['COMP_OCN_OPTION'].value = "(none)"
+    cvars['COMP_ICE_OPTION'].value = "(none)"
+    cvars['COMP_ROF_OPTION'].value = "(none)"
+
+    assert Stage.active().title.startswith('2. Grid')
+
+    cvars['GRID_MODE'].value = 'Standard'
+    cvars['GRID'].value = 'f09_t232'
+
+    assert Stage.active().title.startswith('3. Launch')
+    launch_stage = Stage.active()
+
+    with tempfile.TemporaryDirectory(dir=base_temp_dir) as temp_case_path:
+        pass    # immediately remove the random temporary directory,
+                # which will become the caseroot directory below
+
+    cvars["CASEROOT"].value = temp_case_path
+
+    case_creator = launch_stage._widget._main_body.children[-1]
+    assert isinstance(case_creator, CaseCreatorWidget)
+
+    cvars["PROJECT"].value = "12345"
+
+    # *Click* the create_case button
+    safe_create_case(cime.srcroot, case_creator)
+    
+    # sleep for a bit to allow the case to be created
+    time.sleep(5)
+            
+    # remove the caseroot directory
+    shutil.rmtree(temp_case_path)
+
+
diff --git a/visualCaseGen/custom_widget_types/case_creator.py b/visualCaseGen/custom_widget_types/case_creator.py
index 8205857..e6b5c73 100644
--- a/visualCaseGen/custom_widget_types/case_creator.py
+++ b/visualCaseGen/custom_widget_types/case_creator.py
@@ -508,8 +508,8 @@ def _apply_all_xmlchanges(self, do_exec):
         else:
             assert lnd_grid_mode in [None, "", "Standard"], f"Unknown land grid mode: {lnd_grid_mode}"
 
-        # Set NTASKS based on grid size. e.g. NX * NY < max_pts_per_core
-        if cvars["COMP_OCN"].value == "mom":
+        # Set NTASKS based on grid size if custom ocn grid. e.g. NX * NY < max_pts_per_core
+        if cvars["COMP_OCN"].value == "mom" and cvars["OCN_GRID_MODE"].value == "Custom":
             num_points = int(cvars["OCN_NX"].value) * int(cvars["OCN_NY"].value)
             cores = CaseCreator._calc_cores_based_on_grid(num_points)
             with self._out: