diff --git a/MC/CustomGenerators/PWGGA/Pythia8JJ_EtaPrime.C b/MC/CustomGenerators/PWGGA/Pythia8JJ_EtaPrime.C
index 72bcd872..1e246f7a 100644
--- a/MC/CustomGenerators/PWGGA/Pythia8JJ_EtaPrime.C
+++ b/MC/CustomGenerators/PWGGA/Pythia8JJ_EtaPrime.C
@@ -3,9 +3,13 @@ AliGenerator* GeneratorCustom(TString opt = ""){
     // Pythia
     AliGenerator *gen    = GeneratorPythia8JetsParticleTrg(kPythia8Tune_Monash2013,kCalorimeterAcceptance_FullDetector,331,1.2);
 
-    // settings
-    ((AliGenPythia*) gen)->SetForceDecay(kEtaPrime);
-    
+    // force decay: 
+    // eta prime -> pi plus pi minus eta    100%
+    // eta -> gamma gamma                   100%
+    (AliPythia8::Instance())->ReadString("331:onMode = off");
+    (AliPythia8::Instance())->ReadString("331:onIfMatch = 211 -211 221");
+    (AliPythia8::Instance())->ReadString("221:onMode = off");
+    (AliPythia8::Instance())->ReadString("221:onIfMatch = 22 22");
+
     return gen;
-    
 }