diff --git a/shelfmark/download/clients/deluge.py b/shelfmark/download/clients/deluge.py
index e55104af..bfbae6f6 100644
--- a/shelfmark/download/clients/deluge.py
+++ b/shelfmark/download/clients/deluge.py
@@ -292,11 +292,14 @@ class DelugeClient(DownloadClient):
             # Per-torrent seeding limits from indexer
             seeding_time_limit = coerce_optional_int(kwargs.get("seeding_time_limit"))
             if seeding_time_limit is not None:
-                options["seed_time_limit"] = seeding_time_limit
+                logger.debug(
+                    "Deluge has no per-torrent seeding time limit, ignoring %s minutes",
+                    seeding_time_limit,
+                )
             ratio_limit = coerce_optional_float(kwargs.get("ratio_limit"))
             if ratio_limit is not None:
-                options["stop_at_ratio"] = ratio_limit
-                options["stop_at_ratio_enabled"] = True
+                options["stop_ratio"] = ratio_limit
+                options["stop_at_ratio"] = True
 
             if torrent_info.is_magnet:
                 magnet_url = torrent_info.magnet_url or url
diff --git a/tests/prowlarr/test_deluge_client.py b/tests/prowlarr/test_deluge_client.py
index 4002e9fb..b43e2c99 100644
--- a/tests/prowlarr/test_deluge_client.py
+++ b/tests/prowlarr/test_deluge_client.py
@@ -114,6 +114,82 @@ class TestDelugeClientAddDownload:
             {},
         )
 
+    def test_add_download_sends_ratio_limit_as_stop_ratio(self, monkeypatch):
+        """Ratio limits should use Deluge's stop_ratio float plus the stop_at_ratio switch."""
+        config_values = {
+            "DELUGE_HOST": "http://localhost",
+            "DELUGE_PORT": "8112",
+            "DELUGE_PASSWORD": "password",
+            "DELUGE_CATEGORY": "books",
+        }
+        monkeypatch.setattr(
+            "shelfmark.download.clients.deluge.config.get",
+            make_config_getter(config_values),
+        )
+
+        from shelfmark.download.clients.deluge import DelugeClient
+
+        client = DelugeClient()
+        monkeypatch.setattr(client, "_ensure_connected", lambda: None)
+        mock_rpc_call = MagicMock(return_value="abcdef1234567890abcdef1234567890abcdef12")
+        monkeypatch.setattr(client, "_rpc_call", mock_rpc_call)
+        monkeypatch.setattr(client, "_try_set_label", MagicMock())
+
+        magnet = "magnet:?xt=urn:btih:ABCDEF1234567890ABCDEF1234567890ABCDEF12&dn=test"
+        with patch(
+            "shelfmark.download.clients.deluge.extract_torrent_info", autospec=True
+        ) as mock_extract:
+            mock_extract.return_value = TorrentInfo(
+                info_hash="abcdef1234567890abcdef1234567890abcdef12",
+                torrent_data=None,
+                is_magnet=True,
+                magnet_url=magnet,
+            )
+            client.add_download(magnet, "Test", ratio_limit=1.5)
+
+        mock_rpc_call.assert_called_once_with(
+            "core.add_torrent_magnet",
+            magnet,
+            {"stop_ratio": 1.5, "stop_at_ratio": True},
+        )
+
+    def test_add_download_skips_options_deluge_does_not_define(self, monkeypatch):
+        """Deluge has no per-torrent seeding time limit, so no unknown keys are sent."""
+        config_values = {
+            "DELUGE_HOST": "http://localhost",
+            "DELUGE_PORT": "8112",
+            "DELUGE_PASSWORD": "password",
+            "DELUGE_CATEGORY": "books",
+        }
+        monkeypatch.setattr(
+            "shelfmark.download.clients.deluge.config.get",
+            make_config_getter(config_values),
+        )
+
+        from shelfmark.download.clients.deluge import DelugeClient
+
+        client = DelugeClient()
+        monkeypatch.setattr(client, "_ensure_connected", lambda: None)
+        mock_rpc_call = MagicMock(return_value="abcdef1234567890abcdef1234567890abcdef12")
+        monkeypatch.setattr(client, "_rpc_call", mock_rpc_call)
+        monkeypatch.setattr(client, "_try_set_label", MagicMock())
+
+        magnet = "magnet:?xt=urn:btih:ABCDEF1234567890ABCDEF1234567890ABCDEF12&dn=test"
+        with patch(
+            "shelfmark.download.clients.deluge.extract_torrent_info", autospec=True
+        ) as mock_extract:
+            mock_extract.return_value = TorrentInfo(
+                info_hash="abcdef1234567890abcdef1234567890abcdef12",
+                torrent_data=None,
+                is_magnet=True,
+                magnet_url=magnet,
+            )
+            client.add_download(magnet, "Test", ratio_limit=1.5, seeding_time_limit=120)
+
+        options = mock_rpc_call.call_args.args[2]
+        assert "stop_at_ratio_enabled" not in options
+        assert "seed_time_limit" not in options
+
 
 class TestDelugeClientErrors:
     """Tests for Deluge error handling fallbacks."""