diff --git a/src/simulation/m_surface_tension.fpp b/src/simulation/m_surface_tension.fpp
index e43a39fc1..fb31ffd34 100644
--- a/src/simulation/m_surface_tension.fpp
+++ b/src/simulation/m_surface_tension.fpp
@@ -328,7 +328,7 @@ contains
                     end do
                 end do
             end do
-        elseif (bc_x%beg == -2) then !< slip wall or reflective
+        elseif (bc_x%beg == -2) then ! reflective
             !$acc parallel loop collapse(4) gang vector default(present)
             do i = 1, num_dims + 1
                 do l = 0, p
@@ -391,7 +391,7 @@ contains
                 do l = 0, p
                     do k = 0, n
                         do j = 1, buff_size
-                            if (i == 2) then
+                            if (i == 1) then
                                 c_divs%vf(i)%sf(m + j, k, l) = &
                                    - c_divs%vf(i)%sf(m - (j - 1), k, l)
                             else
@@ -450,8 +450,13 @@ contains
                 do k = 0, p
                     do j = 1, buff_size
                         do l = -buff_size, m + buff_size
-                            c_divs%vf(i)%sf(l, -j, k) = &
-                                c_divs%vf(i)%sf(l, j - 1, k)
+                            if (i == 2) then
+                                c_divs%vf(i)%sf(l, -j, k) = &
+                                  -  c_divs%vf(i)%sf(l, j - 1, k)
+                            else
+                                c_divs%vf(i)%sf(l, -j, k) = &
+                                    c_divs%vf(i)%sf(l, j - 1, k)
+                            endif
                         end do
                     end do
                 end do
@@ -502,8 +507,13 @@ contains
                 do k = 0, p
                     do j = 1, buff_size
                         do l = -buff_size, m + buff_size
-                            c_divs%vf(i)%sf(l, n + j, k) = &
-                                c_divs%vf(i)%sf(l, n - (j - 1), k)
+                            if (i == 2) then
+                                c_divs%vf(i)%sf(l, n + j, k) = &
+                                   - c_divs%vf(i)%sf(l, n - (j - 1), k)
+                            else
+                                c_divs%vf(i)%sf(l, n + j, k) = &
+                                    c_divs%vf(i)%sf(l, n - (j - 1), k)
+                            end if
                         end do
                     end do
                 end do
@@ -568,8 +578,13 @@ contains
                 do j = 1, buff_size
                     do l = -buff_size, n + buff_size
                         do k = -buff_size, m + buff_size
+                            if (i == 3) then
+                                c_divs%vf(i)%sf(k, l, -j) = &
+                                    - c_divs%vf(i)%sf(k, l, j - 1)
+                            else
                                 c_divs%vf(i)%sf(k, l, -j) = &
                                     c_divs%vf(i)%sf(k, l, j - 1)
+                            endif
                         end do
                     end do
                 end do
@@ -620,8 +635,13 @@ contains
                 do j = 1, buff_size
                     do l = -buff_size, n + buff_size
                         do k = -buff_size, m + buff_size
-                            c_divs%vf(i)%sf(k, l, p + j) = &
-                                c_divs%vf(i)%sf(k, l, p - (j - 1))
+                            if (i == 3) then
+                                c_divs%vf(i)%sf(k, l, p + j) = &
+                                    - c_divs%vf(i)%sf(k, l, p - (j - 1))
+                            else
+                                c_divs%vf(i)%sf(k, l, p + j) = &
+                                    c_divs%vf(i)%sf(k, l, p - (j - 1))
+                            endif
                         end do
                     end do
                 end do