diff --git a/ProcessLib/GroundwaterFlow/Tests.cmake b/ProcessLib/GroundwaterFlow/Tests.cmake
index 582c7a1e957d3bc84b80c3a4ef1fccbcefaa2cfd..e6b771e6a7b2a690b742114746090d93bc1e9602 100644
--- a/ProcessLib/GroundwaterFlow/Tests.cmake
+++ b/ProcessLib/GroundwaterFlow/Tests.cmake
@@ -266,7 +266,7 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    cube_1x1x1_hex_1e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_hex_1e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-15 1e-15
+    cube_1x1x1_hex_1e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_hex_1e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux 5e-15 5e-15
 )
 AddTest(
     NAME GroundWaterFlowProcess_cube_1x1x1_1e3_neumann_calculatesurfaceflux
@@ -276,7 +276,7 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    cube_1x1x1_hex_1e3_complete_surface_neumann_specific_flux_t_1.000000.vtu cube_1x1x1_hex_1e3_complete_surface_neumann_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-15 1e-15
+    cube_1x1x1_hex_1e3_complete_surface_neumann_specific_flux_t_1.000000.vtu cube_1x1x1_hex_1e3_complete_surface_neumann_specific_flux_t_1.000000.vtu specific_flux specific_flux 2e-14 2e-14
 )
 AddTest(
     NAME GroundWaterFlowProcess_cube_1x1x1_2e3_prism_surfaceflux_left_right
@@ -286,7 +286,7 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    cube_1x1x1_prism_2e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_prism_2e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-15 1e-15
+    cube_1x1x1_prism_2e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_prism_2e3_complete_surface_left_right_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-14 1e-14
 )
 
 AddTest(
@@ -297,7 +297,7 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    cube_1x1x1_prism_2e3_complete_surface_front_back_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_prism_2e3_complete_surface_front_back_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux  1e-15 1e-15
+    cube_1x1x1_prism_2e3_complete_surface_front_back_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_prism_2e3_complete_surface_front_back_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux  1e-14 1e-14
 )
 
 AddTest(
@@ -308,7 +308,7 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    cube_1x1x1_prism_2e3_complete_surface_top_bottom_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_prism_2e3_complete_surface_top_bottom_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-15 1e-15
+    cube_1x1x1_prism_2e3_complete_surface_top_bottom_dirichlet_specific_flux_t_1.000000.vtu cube_1x1x1_prism_2e3_complete_surface_top_bottom_dirichlet_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-14 1e-14
 )
 
 AddTest(
@@ -319,7 +319,7 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    wedge_1x1x1_1e3_prism_complete_surface_specific_flux_t_1.000000.vtu wedge_1x1x1_1e3_prism_complete_surface_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-15 1e-15
+    wedge_1x1x1_1e3_prism_complete_surface_specific_flux_t_1.000000.vtu wedge_1x1x1_1e3_prism_complete_surface_specific_flux_t_1.000000.vtu specific_flux specific_flux 1e-14 1e-14
 )
 
 # SQUARE 1x1 GROUNDWATER FLOW TEST -- AXIALLY SYMMETRIC