diff --git a/RbcUkqcd.hpp b/RbcUkqcd.hpp
index 85f6f42..5b8d5e1 100644
--- a/RbcUkqcd.hpp
+++ b/RbcUkqcd.hpp
@@ -893,7 +893,7 @@ void RbcUkqcd::addC0LCharmSolver(Application &app, const std::string solverName,
   MAction::ScaledDWF::Par actionPar;
 
   actionPar.gauge = prefix + "_gauge_3stout";
-  actionPar.Ls = 24;
+  actionPar.Ls = 12;
   actionPar.M5 = 1.;
   actionPar.mass = mass;
   actionPar.scale = 2.;