diff --git a/config/config.exs b/config/config.exs
index 49dde36..8e3cd83 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -50,7 +50,7 @@ config :pinchflat, Oban,
     {Oban.Plugins.Pruner, max_age: 30 * 24 * 60 * 60},
     {Oban.Plugins.Cron,
      crontab: [
-       {"@midnight", Pinchflat.Downloading.MediaRetentionWorker}
+       {"@daily", Pinchflat.Downloading.MediaRetentionWorker}
      ]}
   ],
   # TODO: consider making this an env var or something?
diff --git a/lib/pinchflat/downloading/media_retention_worker.ex b/lib/pinchflat/downloading/media_retention_worker.ex
index dd560d3..128d61d 100644
--- a/lib/pinchflat/downloading/media_retention_worker.ex
+++ b/lib/pinchflat/downloading/media_retention_worker.ex
@@ -8,14 +8,30 @@ defmodule Pinchflat.Downloading.MediaRetentionWorker do
 
   require Logger
 
-  # TODO: docs
-  # TODO: test
-  # TODO: set to a 1 min interval to make sure that cron works
+  alias Pinchflat.Media
+
   # TODO: update wiki after this is merged
   # TODO: remove data backfill worker
   # TODO: (other PR - not this one) add way to manually trigger an index of a source AND a pending media download
   # of a source
+  @doc """
+  Deletes media items that are past their retention date and prevents
+  them from being re-downloaded.
+
+  This worker is scheduled to run daily via the Oban Cron plugin.
+
+  Returns :ok
+  """
   @impl Oban.Worker
   def perform(%Oban.Job{}) do
+    cullable_media = Media.list_cullable_media_items()
+    Logger.info("Culling #{length(cullable_media)} media items past their retention date")
+
+    Enum.each(cullable_media, fn media_item ->
+      Media.delete_media_files(media_item, %{
+        prevent_download: true,
+        culled_at: DateTime.utc_now()
+      })
+    end)
   end
 end
diff --git a/lib/pinchflat/media/media.ex b/lib/pinchflat/media/media.ex
index 1caf266..eb0f9c1 100644
--- a/lib/pinchflat/media/media.ex
+++ b/lib/pinchflat/media/media.ex
@@ -22,7 +22,6 @@ defmodule Pinchflat.Media do
     Repo.all(MediaItem)
   end
 
-  # TODO: docs
   # TODO: add attr for excluding media items from this list (ie: keep forever)
   @doc """
   Returns a list of media_items that are cullable based on the retention period
@@ -189,20 +188,19 @@ defmodule Pinchflat.Media do
   Deletes the tasks and media files associated with a media_item but leaves the
   media_item in the database. Does not delete anything to do with associated metadata.
 
-  ## Options:
-    - `:prevent_download` - If `true`, the media_item will be marked to prevent being redownloaded
+  Optionally accepts a second argument `addl_attrs` which will be merged into the
+  media_item before it is updated. Useful for setting things like `prevent_download`
+  and `culled_at`, if wanted
 
   Returns {:ok, %MediaItem{}} | {:error, %Ecto.Changeset{}}
   """
-  def delete_media_files(%MediaItem{} = media_item, opts \\ []) do
-    prevent_download = Keyword.get(opts, :prevent_download, false)
+  def delete_media_files(%MediaItem{} = media_item, addl_attrs \\ %{}) do
     filepath_attrs = MediaItem.filepath_attribute_defaults()
-    opt_attrs = %{prevent_download: prevent_download}
 
     Tasks.delete_tasks_for(media_item)
     {:ok, _} = do_delete_media_files(media_item)
 
-    update_media_item(media_item, Map.merge(filepath_attrs, opt_attrs))
+    update_media_item(media_item, Map.merge(filepath_attrs, addl_attrs))
   end
 
   @doc """
diff --git a/lib/pinchflat/media/media_item.ex b/lib/pinchflat/media/media_item.ex
index 05ab537..595d893 100644
--- a/lib/pinchflat/media/media_item.ex
+++ b/lib/pinchflat/media/media_item.ex
@@ -32,7 +32,8 @@ defmodule Pinchflat.Media.MediaItem do
     :metadata_filepath,
     :nfo_filepath,
     # These are user or system controlled fields
-    :prevent_download
+    :prevent_download,
+    :culled_at
   ]
   # Pretty much all the fields captured at index are required.
   @required_fields ~w(
@@ -73,6 +74,7 @@ defmodule Pinchflat.Media.MediaItem do
     field :subtitle_filepaths, {:array, {:array, :string}}, default: []
 
     field :prevent_download, :boolean, default: false
+    field :culled_at, :utc_datetime
 
     field :matching_search_term, :string, virtual: true
 
diff --git a/lib/pinchflat_web/controllers/media_items/media_item_controller.ex b/lib/pinchflat_web/controllers/media_items/media_item_controller.ex
index d054564..bfcb3d2 100644
--- a/lib/pinchflat_web/controllers/media_items/media_item_controller.ex
+++ b/lib/pinchflat_web/controllers/media_items/media_item_controller.ex
@@ -40,7 +40,7 @@ defmodule PinchflatWeb.MediaItems.MediaItemController do
   def delete(conn, %{"id" => id} = params) do
     prevent_download = Map.get(params, "prevent_download", false)
     media_item = Media.get_media_item!(id)
-    {:ok, _} = Media.delete_media_files(media_item, prevent_download: prevent_download)
+    {:ok, _} = Media.delete_media_files(media_item, %{prevent_download: prevent_download})
 
     conn
     |> put_flash(:info, "Files deleted successfully.")
diff --git a/lib/pinchflat_web/controllers/sources/source_html/index.html.heex b/lib/pinchflat_web/controllers/sources/source_html/index.html.heex
index 3f66720..c912cfb 100644
--- a/lib/pinchflat_web/controllers/sources/source_html/index.html.heex
+++ b/lib/pinchflat_web/controllers/sources/source_html/index.html.heex
@@ -22,6 +22,13 @@
         <:col :let={source} label="Should Download?">
           <.icon name={if source.download_media, do: "hero-check", else: "hero-x-mark"} />
         </:col>
+        <:col :let={source} label="Retention">
+          <%= if source.retention_period_days && source.retention_period_days > 0 do %>
+            <%= source.retention_period_days %> day(s)
+          <% else %>
+            <span class="text-lg">∞</span>
+          <% end %>
+        </:col>
         <:col :let={source} label="Media Profile">
           <.subtle_link href={~p"/media_profiles/#{source.media_profile_id}"}>
             <%= source.media_profile.name %>
diff --git a/lib/pinchflat_web/controllers/sources/source_html/source_form.html.heex b/lib/pinchflat_web/controllers/sources/source_html/source_form.html.heex
index cd16370..11374ef 100644
--- a/lib/pinchflat_web/controllers/sources/source_html/source_form.html.heex
+++ b/lib/pinchflat_web/controllers/sources/source_html/source_form.html.heex
@@ -93,7 +93,7 @@
     type="number"
     label="Retention Period (days)"
     min="0"
-    help="Days between when media is *downloaded* and when it's deleted. Set to 0 or delete to keep media indefinitely"
+    help="Days between when media is *downloaded* and when it's deleted. Delete to keep media forever"
   />
 
   <section x-show="advancedMode">
diff --git a/priv/repo/migrations/20240403164943_add_culled_at_to_media_items.exs b/priv/repo/migrations/20240403164943_add_culled_at_to_media_items.exs
new file mode 100644
index 0000000..8ac2d6f
--- /dev/null
+++ b/priv/repo/migrations/20240403164943_add_culled_at_to_media_items.exs
@@ -0,0 +1,9 @@
+defmodule Pinchflat.Repo.Migrations.AddCulledAtToMediaItems do
+  use Ecto.Migration
+
+  def change do
+    alter table(:media_items) do
+      add :culled_at, :utc_datetime
+    end
+  end
+end
diff --git a/test/pinchflat/downloading/media_retention_worker_test.exs b/test/pinchflat/downloading/media_retention_worker_test.exs
new file mode 100644
index 0000000..e0aa5c2
--- /dev/null
+++ b/test/pinchflat/downloading/media_retention_worker_test.exs
@@ -0,0 +1,58 @@
+defmodule Pinchflat.Downloading.MediaRetentionWorkerTest do
+  use Pinchflat.DataCase
+
+  import Pinchflat.MediaFixtures
+  import Pinchflat.SourcesFixtures
+
+  alias Pinchflat.Downloading.MediaRetentionWorker
+
+  describe "perform/1" do
+    test "deletes media files that are past their retention date" do
+      {_source, old_media_item, new_media_item} = prepare_records()
+
+      perform_job(MediaRetentionWorker, %{})
+
+      assert File.exists?(new_media_item.media_filepath)
+      refute File.exists?(old_media_item.media_filepath)
+      assert Repo.reload!(new_media_item).media_filepath
+      refute Repo.reload!(old_media_item).media_filepath
+    end
+
+    test "sets deleted media to not re-download" do
+      {_source, old_media_item, new_media_item} = prepare_records()
+
+      perform_job(MediaRetentionWorker, %{})
+
+      refute Repo.reload!(new_media_item).prevent_download
+      assert Repo.reload!(old_media_item).prevent_download
+    end
+
+    test "sets culled_at timestamp on deleted media" do
+      {_source, old_media_item, new_media_item} = prepare_records()
+
+      perform_job(MediaRetentionWorker, %{})
+
+      refute Repo.reload!(new_media_item).culled_at
+      assert Repo.reload!(old_media_item).culled_at
+      assert DateTime.diff(now(), Repo.reload!(old_media_item).culled_at) < 1
+    end
+  end
+
+  defp prepare_records do
+    source = source_fixture(%{retention_period_days: 2})
+
+    old_media_item =
+      media_item_with_attachments(%{
+        source_id: source.id,
+        media_downloaded_at: now_minus(3, :days)
+      })
+
+    new_media_item =
+      media_item_with_attachments(%{
+        source_id: source.id,
+        media_downloaded_at: now_minus(1, :day)
+      })
+
+    {source, old_media_item, new_media_item}
+  end
+end
diff --git a/test/pinchflat/media_test.exs b/test/pinchflat/media_test.exs
index 9a17ca9..35bd3dd 100644
--- a/test/pinchflat/media_test.exs
+++ b/test/pinchflat/media_test.exs
@@ -699,6 +699,7 @@ defmodule Pinchflat.MediaTest do
     test "deletes the media_item's files" do
       media_item = media_item_with_attachments()
 
+      assert File.exists?(media_item.media_filepath)
       assert {:ok, _} = Media.delete_media_files(media_item)
       refute File.exists?(media_item.media_filepath)
     end
@@ -728,10 +729,10 @@ defmodule Pinchflat.MediaTest do
       Media.delete_media_item(updated_media_item, delete_files: true)
     end
 
-    test "can prevent the media item from being downloaded" do
+    test "can take additional attributes update media item" do
       media_item = media_item_with_attachments()
 
-      assert {:ok, updated_media_item} = Media.delete_media_files(media_item, prevent_download: true)
+      assert {:ok, updated_media_item} = Media.delete_media_files(media_item, %{prevent_download: true})
       assert updated_media_item.prevent_download
     end
   end