diff --git a/idtxl/network_analysis.py b/idtxl/network_analysis.py
index f2cef002..e4329807 100644
--- a/idtxl/network_analysis.py
+++ b/idtxl/network_analysis.py
@@ -303,7 +303,8 @@ def _remove_forced_conditionals(self, candidate_set):
             cond = self.settings['add_conditionals']
             if type(cond) is tuple:  # easily add single variable
                 cond = [cond]
-            candidate_set = list(set(candidate_set).difference(set(cond)))
+            cond_idx = self._lag_to_idx(cond)            
+            candidate_set = list(set(candidate_set).difference(set(cond_idx)))
         return candidate_set
 
     def _append_selected_vars_idx(self, idx):
diff --git a/test/test_active_information_storage.py b/test/test_active_information_storage.py
index 5aeaddf7..ebbcc2b2 100644
--- a/test/test_active_information_storage.py
+++ b/test/test_active_information_storage.py
@@ -255,26 +255,27 @@ def test_define_candidates():
     # Test if candidates that are added manually to the conditioning set are
     # removed from the candidate set.
     nw = ActiveInformationStorage()
+    nw.current_value = current_val
     settings = [
         {'add_conditionals': None},
         {'add_conditionals': (2, 3)},
-        {'add_conditionals': [(2, 3), (4, 1)]}]
+        {'add_conditionals': [(2, 3), (4, 1)]},
+        {'add_conditionals': [(1, 9)]},
+        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
     for s in settings:
         nw.settings = s
         candidates = nw._define_candidates(procs, samples)
         assert (1, 9) in candidates, 'Sample missing from candidates: (1, 9).'
         assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
         assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
-
-    settings = [
-        {'add_conditionals': [(1, 9)]},
-        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
-    for s in settings:
-        nw.settings = s
-        candidates = nw._define_candidates(procs, samples)
-    assert (1, 9) not in candidates, 'Sample missing from candidates: (1, 9).'
-    assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
-    assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
+        if s['add_conditionals'] is not None:
+            if type(s['add_conditionals']) is tuple:
+                cond_ind = nw._lag_to_idx([s['add_conditionals']])
+            else:
+                cond_ind = nw._lag_to_idx(s['add_conditionals'])
+            for c in cond_ind:
+                assert c not in candidates, (
+                    'Sample added erronously to candidates: {}.'.format(c))
 
 
 if __name__ == '__main__':
diff --git a/test/test_bivariate_mi.py b/test/test_bivariate_mi.py
index e3562a84..e7535f28 100644
--- a/test/test_bivariate_mi.py
+++ b/test/test_bivariate_mi.py
@@ -372,26 +372,27 @@ def test_define_candidates():
     # Test if candidates that are added manually to the conditioning set are
     # removed from the candidate set.
     nw = BivariateMI()
+    nw.current_value = current_val
     settings = [
         {'add_conditionals': None},
         {'add_conditionals': (2, 3)},
-        {'add_conditionals': [(2, 3), (4, 1)]}]
+        {'add_conditionals': [(2, 3), (4, 1)]},
+        {'add_conditionals': [(1, 9)]},
+        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
     for s in settings:
         nw.settings = s
         candidates = nw._define_candidates(procs, samples)
         assert (1, 9) in candidates, 'Sample missing from candidates: (1, 9).'
         assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
         assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
-
-    settings = [
-        {'add_conditionals': [(1, 9)]},
-        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
-    for s in settings:
-        nw.settings = s
-        candidates = nw._define_candidates(procs, samples)
-    assert (1, 9) not in candidates, 'Sample missing from candidates: (1, 9).'
-    assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
-    assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
+        if s['add_conditionals'] is not None:
+            if type(s['add_conditionals']) is tuple:
+                cond_ind = nw._lag_to_idx([s['add_conditionals']])
+            else:
+                cond_ind = nw._lag_to_idx(s['add_conditionals'])
+            for c in cond_ind:
+                assert c not in candidates, (
+                    'Sample added erronously to candidates: {}.'.format(c))
 
 @jpype_missing
 def test_analyse_network():
diff --git a/test/test_bivariate_te.py b/test/test_bivariate_te.py
index 8cc22f9c..2b89599f 100644
--- a/test/test_bivariate_te.py
+++ b/test/test_bivariate_te.py
@@ -372,26 +372,27 @@ def test_define_candidates():
     # Test if candidates that are added manually to the conditioning set are
     # removed from the candidate set.
     nw = BivariateTE()
+    nw.current_value = current_val
     settings = [
         {'add_conditionals': None},
         {'add_conditionals': (2, 3)},
-        {'add_conditionals': [(2, 3), (4, 1)]}]
+        {'add_conditionals': [(2, 3), (4, 1)]},
+        {'add_conditionals': [(1, 9)]},
+        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
     for s in settings:
         nw.settings = s
         candidates = nw._define_candidates(procs, samples)
         assert (1, 9) in candidates, 'Sample missing from candidates: (1, 9).'
         assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
         assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
-
-    settings = [
-        {'add_conditionals': [(1, 9)]},
-        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
-    for s in settings:
-        nw.settings = s
-        candidates = nw._define_candidates(procs, samples)
-    assert (1, 9) not in candidates, 'Sample missing from candidates: (1, 9).'
-    assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
-    assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
+        if s['add_conditionals'] is not None:
+            if type(s['add_conditionals']) is tuple:
+                cond_ind = nw._lag_to_idx([s['add_conditionals']])
+            else:
+                cond_ind = nw._lag_to_idx(s['add_conditionals'])
+            for c in cond_ind:
+                assert c not in candidates, (
+                    'Sample added erronously to candidates: {}.'.format(c))
 
 
 @jpype_missing
diff --git a/test/test_multivariate_mi.py b/test/test_multivariate_mi.py
index 83e9e0b0..a7d037d3 100644
--- a/test/test_multivariate_mi.py
+++ b/test/test_multivariate_mi.py
@@ -363,26 +363,27 @@ def test_define_candidates():
     # Test if candidates that are added manually to the conditioning set are
     # removed from the candidate set.
     nw = MultivariateMI()
+    nw.current_value = current_val
     settings = [
         {'add_conditionals': None},
         {'add_conditionals': (2, 3)},
-        {'add_conditionals': [(2, 3), (4, 1)]}]
+        {'add_conditionals': [(2, 3), (4, 1)]},
+        {'add_conditionals': [(1, 9)]},
+        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
     for s in settings:
         nw.settings = s
         candidates = nw._define_candidates(procs, samples)
         assert (1, 9) in candidates, 'Sample missing from candidates: (1, 9).'
         assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
         assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
-
-    settings = [
-        {'add_conditionals': [(1, 9)]},
-        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
-    for s in settings:
-        nw.settings = s
-        candidates = nw._define_candidates(procs, samples)
-    assert (1, 9) not in candidates, 'Sample missing from candidates: (1, 9).'
-    assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
-    assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
+        if s['add_conditionals'] is not None:
+            if type(s['add_conditionals']) is tuple:
+                cond_ind = nw._lag_to_idx([s['add_conditionals']])
+            else:
+                cond_ind = nw._lag_to_idx(s['add_conditionals'])
+            for c in cond_ind:
+                assert c not in candidates, (
+                    'Sample added erronously to candidates: {}.'.format(c))
 
 
 @jpype_missing
diff --git a/test/test_multivariate_te.py b/test/test_multivariate_te.py
index 731a8a45..33a5d33f 100644
--- a/test/test_multivariate_te.py
+++ b/test/test_multivariate_te.py
@@ -368,26 +368,27 @@ def test_define_candidates():
     # Test if candidates that are added manually to the conditioning set are
     # removed from the candidate set.
     nw = MultivariateTE()
+    nw.current_value = current_val
     settings = [
         {'add_conditionals': None},
         {'add_conditionals': (2, 3)},
-        {'add_conditionals': [(2, 3), (4, 1)]}]
+        {'add_conditionals': [(2, 3), (4, 1)]},
+        {'add_conditionals': [(1, 9)]},
+        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
     for s in settings:
         nw.settings = s
         candidates = nw._define_candidates(procs, samples)
         assert (1, 9) in candidates, 'Sample missing from candidates: (1, 9).'
         assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
         assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
-
-    settings = [
-        {'add_conditionals': [(1, 9)]},
-        {'add_conditionals': [(1, 9), (2, 3), (4, 1)]}]
-    for s in settings:
-        nw.settings = s
-        candidates = nw._define_candidates(procs, samples)
-    assert (1, 9) not in candidates, 'Sample missing from candidates: (1, 9).'
-    assert (1, 6) in candidates, 'Sample missing from candidates: (1, 6).'
-    assert (1, 3) in candidates, 'Sample missing from candidates: (1, 3).'
+        if s['add_conditionals'] is not None:
+            if type(s['add_conditionals']) is tuple:
+                cond_ind = nw._lag_to_idx([s['add_conditionals']])
+            else:
+                cond_ind = nw._lag_to_idx(s['add_conditionals'])
+            for c in cond_ind:
+                assert c not in candidates, (
+                    'Sample added erronously to candidates: {}.'.format(c))
 
 
 @jpype_missing