diff --git a/virtualizarr/zarr.py b/virtualizarr/zarr.py
index 932e7da5..e5015b36 100644
--- a/virtualizarr/zarr.py
+++ b/virtualizarr/zarr.py
@@ -90,7 +90,7 @@ def __post_init__(self) -> None:
     @model_validator(mode="after")
     def _check_fill_value(self) -> Self:
         if self.fill_value is None:
-            self.fill_value = ZARR_DEFAULT_FILL_VALUE.get(self.dtype, default=0.0)
+            self.fill_value = ZARR_DEFAULT_FILL_VALUE.get(self.dtype, 0.0)
         return self
 
     @property