diff --git a/sota-implementations/td3/config.yaml b/sota-implementations/td3/config.yaml
index ba2db81b489..8207a41a9f5 100644
--- a/sota-implementations/td3/config.yaml
+++ b/sota-implementations/td3/config.yaml
@@ -21,7 +21,7 @@ collector:
 replay_buffer:
   prb: 0 # use prioritized experience replay
   size: 1000000
-  scratch_dir:
+  scratch_dir: null
 
 # optim
 optim:
diff --git a/sota-implementations/td3/utils.py b/sota-implementations/td3/utils.py
index 8395d9eeaec..071bad6c68b 100644
--- a/sota-implementations/td3/utils.py
+++ b/sota-implementations/td3/utils.py
@@ -144,7 +144,7 @@ def make_replay_buffer(
         prefetch = 0
     with (
         tempfile.TemporaryDirectory()
-        if scratch_dir is None
+        if scratch_dir in ("", None)
         else nullcontext(scratch_dir)
     ) as scratch_dir:
         storage_cls = (