diff --git a/gracedb/superevents/migrations/0005_add_coinc_far_and_em_type.py b/gracedb/superevents/migrations/0005_add_coinc_far_and_em_type.py
index 71589d2d4fe6e1891e2359ff2324d8069797d4fb..7446360561e9fe1adfc64873789bb5a1cf2e8c15 100644
--- a/gracedb/superevents/migrations/0005_add_coinc_far_and_em_type.py
+++ b/gracedb/superevents/migrations/0005_add_coinc_far_and_em_type.py
@@ -21,6 +21,6 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='Superevent',
             name='em_type',
-            field=models.CharField(blank=True, default=b'', max_length=100),
+            field=models.CharField(null=True, blank=True, max_length=100),
         ),
     ]
diff --git a/gracedb/superevents/models.py b/gracedb/superevents/models.py
index 2e2e119018835a8dc96e6e6b8b4c99d1ff57b32d..baffbef11fc3dc97b29870d7192393e5c9ced214 100644
--- a/gracedb/superevents/models.py
+++ b/gracedb/superevents/models.py
@@ -113,8 +113,8 @@ class Superevent(CleanSaveModel, AutoIncrementModel):
     is_exposed = models.BooleanField(default=False)
 
     # New O3b fields for RAVEN:
-    coinc_far = models.FloatField(null=True, blank=True)
-    em_type = models.CharField(blank=True, default=b'', max_length=100)
+    coinc_far = models.FloatField(null=False, blank=True)
+    em_type = models.CharField(blank=True, null=True, max_length=100)
 
     # Meta class --------------------------------------------------------------
     class Meta: