diff --git a/pepfar_mle/common/admin.py b/pepfar_mle/common/admin.py
index 3d50f82a..5a002d90 100644
--- a/pepfar_mle/common/admin.py
+++ b/pepfar_mle/common/admin.py
@@ -4,6 +4,13 @@
 
 
 class BaseAdmin(admin.ModelAdmin):
+    readonly_fields = (
+        "created",
+        "created_by",
+        "updated",
+        "updated_by",
+    )
+
     def save_model(self, request, obj, form, change):
         if not change:
             obj.created_by = request.user.pk
diff --git a/pepfar_mle/common/migrations/0005_auto_20210714_1633.py b/pepfar_mle/common/migrations/0005_auto_20210714_1633.py
new file mode 100644
index 00000000..4b9c2cd5
--- /dev/null
+++ b/pepfar_mle/common/migrations/0005_auto_20210714_1633.py
@@ -0,0 +1,18 @@
+# Generated by Django 3.1.12 on 2021-07-14 13:33
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('common', '0004_auto_20210714_1339'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='facilityattachment',
+            name='size',
+            field=models.IntegerField(blank=True, help_text='The size of the attachment in bytes', null=True),
+        ),
+    ]
diff --git a/pepfar_mle/common/models.py b/pepfar_mle/common/models.py
index 11edb4fc..c146e8b0 100644
--- a/pepfar_mle/common/models.py
+++ b/pepfar_mle/common/models.py
@@ -318,7 +318,9 @@ class Attachment(AbstractBase):
     data = models.FileField(upload_to=get_directory, max_length=65535)
     title = models.CharField(max_length=255)
     creation_date = models.DateTimeField(default=timezone.now)
-    size = models.IntegerField(help_text="The size of the attachment in bytes")
+    size = models.IntegerField(
+        help_text="The size of the attachment in bytes", null=True, blank=True
+    )
     description = models.TextField(null=True, blank=True)
     aspect_ratio = models.CharField(max_length=50, blank=True, null=True)
 
@@ -328,7 +330,10 @@ def validate_image_size(self):
         """Ensure that the supplied image size matches the actual file."""
         if not is_image_type(self.content_type):
             return
+
         image = Image.open(self.data)
+        self.size = len(image.fp.read())
+
         width, height = image.size
         msg_template = (
             "Your image has a {axis} of {actual_size} {extra_text} "