diff --git a/spimquant/config/snakebids.yml b/spimquant/config/snakebids.yml
index 1d08a15..f97d7f2 100644
--- a/spimquant/config/snakebids.yml
+++ b/spimquant/config/snakebids.yml
@@ -245,9 +245,9 @@ parse_args:
     help: "Chunk size (c, x, y, z) for intermediate OME-Zarr stores (default: %(default)s)"
     default:
       - 1
-      - 128
-      - 128
-      - 128
+      - 256
+      - 256
+      - 256
     nargs: 4
     type: int
     dest: zarr_store_chunks