diff --git a/modules/system/default.nix b/modules/system/default.nix
index 142b407..679b5b7 100644
--- a/modules/system/default.nix
+++ b/modules/system/default.nix
@@ -21,7 +21,7 @@
     gc = {
       automatic = true;
       dates = "weekly";
-      options = "--delete-older-than 7d";
+      options = "--delete-older-than 30d";
     };
     settings.auto-optimise-store = true;
   };