diff --git a/generic_tracers/generic_COBALT.F90 b/generic_tracers/generic_COBALT.F90
index d3ccec3..e3d578e 100644
--- a/generic_tracers/generic_COBALT.F90
+++ b/generic_tracers/generic_COBALT.F90
@@ -9764,12 +9764,14 @@ subroutine generic_COBALT_update_from_source(tracer_list,Temp,Salt,tv,rho_dzt,dz
     !
     ! Iceberg and "Coastal" iron and other nutrient input
     !
-    do j = jsc, jec ; do i = isc, iec
-       cobalt%jfe_iceberg(i,j,1) = cobalt%jfe_iceberg_ratio*max(frunoff(i,j),0.0)/rho_dzt(i,j,1)
-       cobalt%jno3_iceberg(i,j,1) = cobalt%jno3_iceberg_ratio*max(frunoff(i,j),0.0)/rho_dzt(i,j,1)
-       cobalt%jpo4_iceberg(i,j,1) = cobalt%jpo4_iceberg_ratio*max(frunoff(i,j),0.0)/rho_dzt(i,j,1)
-       cobalt%jfe_coast(i,j,1) = cobalt%fe_coast * mask_coast(i,j) * grid_tmask(i,j,1) / &
-            sqrt(grid_dat(i,j))
+    do j = jsc, jec ; do i = isc, iec !{
+       if (grid_kmt(i,j) .gt. 0) then !{
+          cobalt%jfe_iceberg(i,j,1) = cobalt%jfe_iceberg_ratio*max(frunoff(i,j),0.0)/rho_dzt(i,j,1)
+          cobalt%jno3_iceberg(i,j,1) = cobalt%jno3_iceberg_ratio*max(frunoff(i,j),0.0)/rho_dzt(i,j,1)
+          cobalt%jpo4_iceberg(i,j,1) = cobalt%jpo4_iceberg_ratio*max(frunoff(i,j),0.0)/rho_dzt(i,j,1)
+          cobalt%jfe_coast(i,j,1) = cobalt%fe_coast * mask_coast(i,j) * grid_tmask(i,j,1) / &
+               sqrt(grid_dat(i,j))
+       endif !}
     enddo; enddo  !} i,j
     do k = 2, nk ; do j = jsc, jec ; do i = isc, iec   !{
        cobalt%jfe_coast(i,j,k) = cobalt%fe_coast * mask_coast(i,j) * grid_tmask(i,j,k) / &