diff --git a/.github/workflows/test_valgrind.yml b/.github/workflows/test_valgrind.yml
index 4429e56e4f..94cac89a40 100644
--- a/.github/workflows/test_valgrind.yml
+++ b/.github/workflows/test_valgrind.yml
@@ -21,22 +21,40 @@ name: valgrind check
 #  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 
 on:
+  # Allows you to run this workflow manually.
+  workflow_dispatch:
+    inputs:
+      MAKEFLAGS:
+        type: string
+        description: 'Make flags to use for compilation (like -j4)'
+        default: '-j4'
+      MPI:
+        type: string
+        description: 'Use MPI for compilation (ON/OFF)'
+        default: 'ON'
+      BUILD_TYPE:
+        type: string
+        description: 'Build type (Release/Debug)'
+        default: 'Debug'
+      TEST_LEVEL:
+        type: string
+        description: 'Test level used for configuring (T8_TEST_LEVEL_FULL, T8_TEST_LEVEL_MEDIUM, or T8_TEST_LEVEL_BASIC)'
+        default: 'T8_TEST_LEVEL_BASIC'
   workflow_call:
     inputs:
       MAKEFLAGS:
-        required: true
         type: string
         description: 'Make flags to use for compilation (like -j4)'
+        default: '-j4'
       MPI:
-        required: true
         type: string
         description: 'Use MPI for compilation (ON/OFF)'
+        default: 'ON'
       BUILD_TYPE:
-        required: true
         type: string
         description: 'Build type (Release/Debug)'
+        default: 'Debug'
       TEST_LEVEL:
-        required: true
         type: string
         description: 'Test level used for configuring (T8_TEST_LEVEL_FULL, T8_TEST_LEVEL_MEDIUM, or T8_TEST_LEVEL_BASIC)'
         default: 'T8_TEST_LEVEL_FULL'
@@ -101,9 +119,7 @@ jobs:
         path: build/CMakeFiles/CMakeOutput.log
     - name: ninja
       run: cd build && ninja $MAKEFLAGS
-    - name: ninja install
-      run: cd build && ninja install $MAKEFLAGS
     # Execute script that runs a Valgrind check for all test binaries.
-    # We use 3 parallel processes to run the binaries in parallel with MPI.
+    # We use 4 parallel processes to run the binaries in parallel with MPI.
     - name: Valgrind check
-      run: cd scripts && bash ./check_all_test_binaries_valgrind.sh --ntasks=3
+      run: cd scripts && bash ./check_all_test_binaries_valgrind.sh --ntasks=4
diff --git a/.github/workflows/testsuite.yml b/.github/workflows/testsuite.yml
index 4c10076a54..b3ab042463 100644
--- a/.github/workflows/testsuite.yml
+++ b/.github/workflows/testsuite.yml
@@ -194,9 +194,6 @@ jobs:
     needs: preparation
     uses: ./.github/workflows/test_valgrind.yml
     with:
-      MAKEFLAGS: -j4
-      MPI: ON
-      BUILD_TYPE: Debug
       TEST_LEVEL: T8_TEST_LEVEL_BASIC # Do Valgrind check for test level T8_TEST_LEVEL_BASIC for performance reasons.
 
   # Generate code coverage and deploy to Codecov.
diff --git a/scripts/README.md b/scripts/README.md
index 5f6633ac61..c573496467 100644
--- a/scripts/README.md
+++ b/scripts/README.md
@@ -51,7 +51,7 @@ The paths are relative paths assuming an execution from the test/ folder in the
 #### check_all_test_binaries_valgrind.sh
 
 This script performs a valgrind check on each test binary found by [find_all_test_binary_paths.sh](find_all_test_binary_paths.sh).
-The valgrind check is done by [check_valgrind.sh](check_valgrind.sh). It is assumed that the build folder ../build/test/ with the correct test binaries exists. With `--ntasks=[NUMBER]`, you can provide the number of processes to use with mpi (default is 1).
+The valgrind check is done by [check_valgrind.sh](check_valgrind.sh). It is assumed that the build folder ../build/test/ with the correct test binaries exists. With `--ntasks=[NUMBER]`, you can provide the number of processes to use with mpi for parallel tests (default is 1).
 
 ## Others
 
diff --git a/scripts/check_all_test_binaries_valgrind.sh b/scripts/check_all_test_binaries_valgrind.sh
index f0b39cffe2..c4f5796b30 100644
--- a/scripts/check_all_test_binaries_valgrind.sh
+++ b/scripts/check_all_test_binaries_valgrind.sh
@@ -26,12 +26,12 @@
 # The script returns 1 if an error is found and 0 otherwise. 
 # This script must be executed from the scripts/ folder.
 # It is assumed that the build folder ../build/test/ with the correct test binaries exists.
-# With "--ntasks=[NUMBER]", you can provide the number of processes to use with MPI (default is 1).
+# With "--ntasks=[NUMBER]", you can provide the number of processes to use with MPI for parallel tests (default is 1).
 #
 
 USAGE="\nUSAGE: This script executes valgrind in parallel on each test binary available. Use the syntax \n
 $0 --ntasks=[NUM_TASKS]\n 
-Providing the number of parallel processes to use with MPI is optional.\n"
+Providing the number of parallel processes to use with MPI for parallel tests is optional.\n"
 
 # Check if a number of processes is provided. If not, set to 1.
 num_procs=1
@@ -79,16 +79,39 @@ status=0
 counter=0
 valgrind_suppressions_file=../../scripts/valgrind_suppressions_file.supp
 
+# First run all serial tests in parallel.
+serial_count=$(echo $test_bin_paths | tr ' ' '\n' | grep -c '_serial')
+echo "Running valgrind checks on $serial_count serial test binaries in parallel..."
 for bin_path in $test_bin_paths; do
-  counter=$(( $counter + 1 ))
-  echo -n "[$counter/$num_paths] "
-  # Run check_valgrind script for each test binary.
-  bash ../../scripts/check_valgrind.sh $bin_path --supp=$valgrind_suppressions_file --ntasks=$num_procs 2>&1
-  status=$?
-  # If status is not 0, an error occurred.
-  if test $status -ne 0; then
-    echo "Error occurred during the valgrind check of $bin_path."
-    exit 1
+  if [[ $bin_path == *"_serial"* ]]; then
+    counter=$(( $counter + 1 ))
+    # Run check_valgrind script for each test binary. The & at the end allows parallel execution.
+    bash ../../scripts/check_valgrind.sh $bin_path --supp=$valgrind_suppressions_file --ntasks=1 2>&1 &
+    status=$?
+    # If status is not 0, an error occurred.
+    if test $status -ne 0; then
+      echo "Error occurred during the valgrind check of $bin_path."
+      kill $(jobs -p)
+      exit 1
+    fi
+  fi
+done
+# Wait until all serial valgrind checks are done.
+wait
+echo "Valgrind found no errors in the ${counter} serial test executables."
+echo "Check remaining parallel tests."
+for bin_path in $test_bin_paths; do
+  if [[ $bin_path == *"_parallel"* ]]; then
+    counter=$(( $counter + 1 ))
+    echo -n "[$counter/$num_paths] "
+    # Run check_valgrind script for each test binary.
+    bash ../../scripts/check_valgrind.sh $bin_path --supp=$valgrind_suppressions_file --ntasks=$num_procs 2>&1
+    status=$?
+    # If status is not 0, an error occurred.
+    if test $status -ne 0; then
+      echo "Error occurred during the valgrind check of $bin_path."
+      exit 1
+    fi
   fi
 done
 
diff --git a/scripts/check_valgrind.sh b/scripts/check_valgrind.sh
index 8e96fe21c7..635bdfd34b 100644
--- a/scripts/check_valgrind.sh
+++ b/scripts/check_valgrind.sh
@@ -83,7 +83,7 @@ done
 echo "Valgrind check of ${FILE} using ${num_procs} processes..."
 
 # Write valgrind output to variable OUTPUT_FILE.
-OUTPUT_FILE="valgrind-output.log"
+OUTPUT_FILE="valgrind-output-$(basename "$FILE").log"
 # Set valgrind flags.
 VALGRIND_FLAGS="${VALGRIND_FLAGS} --leak-check=full --track-origins=yes \
     --trace-children=yes --show-leak-kinds=definite,indirect,possible \