diff --git a/model/common/pyproject.toml b/model/common/pyproject.toml
index 48b790d359..d0c8aeac09 100644
--- a/model/common/pyproject.toml
+++ b/model/common/pyproject.toml
@@ -43,7 +43,7 @@ version = "0.0.6"
 all = ["icon4py-common[distributed,io]"]
 cuda11 = ['cupy-cuda11x>=13.0', 'gt4py[cuda11]']
 cuda12 = ['cupy-cuda12x>=13.0', 'gt4py[cuda12]']
-distributed = ["ghex>=0.5.0", "mpi4py>=3.1.5"]
+distributed = ["ghex>=0.5.1", "mpi4py>=3.1.5"]
 io = [
   # external dependencies
   "cartopy>=0.22.0",
diff --git a/model/common/src/icon4py/model/common/decomposition/definitions.py b/model/common/src/icon4py/model/common/decomposition/definitions.py
index 0c7179988d..9ebc5f40c8 100644
--- a/model/common/src/icon4py/model/common/decomposition/definitions.py
+++ b/model/common/src/icon4py/model/common/decomposition/definitions.py
@@ -75,7 +75,7 @@ class Stream:
     ptr: int
 
     def __cuda_stream__(self) -> tuple[int, int]:
-        return 1, self.ptr
+        return 0, self.ptr
 
 
 DEFAULT_STREAM = Stream(0)
diff --git a/uv.lock b/uv.lock
index d5c216e846..adb7d13bef 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1386,13 +1386,13 @@ wheels = [
 
 [[package]]
 name = "ghex"
-version = "0.5.0"
+version = "0.5.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "mpi4py" },
     { name = "numpy" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/7c/45/834e3c9c67e3ea329a6ba778155d2e472d107165b7824bdd3d9029afa0a2/ghex-0.5.0.tar.gz", hash = "sha256:e877e46cf46cd80d16671d3537c0b0e5cec9a0fc5f04b873052ab363de7f5f79", size = 8911842, upload-time = "2026-03-18T08:29:41.269Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/23/50/a1af817b283d4db8a40561fe5c1d0630359d455aadaa4d9cdaf51a11d9f0/ghex-0.5.1.tar.gz", hash = "sha256:1a7e96b39f3c98a885237c98e8c7b0da24a5d06d2770c496707f47a42951466c", size = 8912044, upload-time = "2026-03-26T13:49:18.161Z" }
 
 [[package]]
 name = "gitdb"
@@ -1932,7 +1932,7 @@ requires-dist = [
     { name = "cupy-cuda12x", marker = "extra == 'cuda12'", specifier = ">=13.0" },
     { name = "dace", specifier = "==43!2026.2.12", index = "https://gridtools.github.io/pypi/" },
     { name = "datashader", marker = "extra == 'io'", specifier = ">=0.16.1" },
-    { name = "ghex", marker = "extra == 'distributed'", specifier = ">=0.5.0" },
+    { name = "ghex", marker = "extra == 'distributed'", specifier = ">=0.5.1" },
     { name = "gt4py", specifier = "==1.1.8" },
     { name = "gt4py", extras = ["cuda11"], marker = "extra == 'cuda11'" },
     { name = "gt4py", extras = ["cuda12"], marker = "extra == 'cuda12'" },