diff --git a/tardis/energy_input/gamma_ray_packet_source.py b/tardis/energy_input/gamma_ray_packet_source.py
index 71d274091b7..888b4eb4cbb 100644
--- a/tardis/energy_input/gamma_ray_packet_source.py
+++ b/tardis/energy_input/gamma_ray_packet_source.py
@@ -253,7 +253,7 @@ def create_packets(self, decays_per_isotope, *args, **kwargs):
             Array of positron output dataframe rows
         """
         number_of_packets = decays_per_isotope.sum().sum()
-        decays_per_shell = decays_per_isotope.T.sum().values
+        decays_per_shell = decays_per_isotope.sum().values
 
         locations = np.zeros((3, number_of_packets))
         directions = np.zeros((3, number_of_packets))
diff --git a/tardis/energy_input/main_gamma_ray_loop.py b/tardis/energy_input/main_gamma_ray_loop.py
index 3d8bd9badf0..4ae1ba8235c 100644
--- a/tardis/energy_input/main_gamma_ray_loop.py
+++ b/tardis/energy_input/main_gamma_ray_loop.py
@@ -152,7 +152,7 @@ def run_gamma_ray_loop(
     logger.info("Initializing packets")
 
     packet_source = RadioactivePacketSource(
-        energy_per_packet,
+        individual_packet_energy,
         gamma_ray_line_dict,
         positronium_fraction,
         inner_velocities,
@@ -174,8 +174,8 @@ def run_gamma_ray_loop(
 
     logger.info("Creating packet list")
     packets = []
-    total_cmf_energy = 0.0
-    total_rf_energy = 0.0
+    total_cmf_energy = packet_collection.energy_cmf.sum()
+    total_rf_energy = packet_collection.energy_rf.sum()
     for i in range(number_of_packets):
         packet = GXPacket(
             packet_collection.location[:, i],
@@ -201,8 +201,6 @@ def run_gamma_ray_loop(
                 0,
             ]
         )
-        total_cmf_energy += packet.energy_cmf
-        total_rf_energy += packet.energy_rf
 
     logger.info(f"Total cmf energy is {total_cmf_energy}")
     logger.info(f"Total rf energy is {total_rf_energy}")