diff --git a/src/indicators/migrations/0004_alter_indicator_base.py b/src/indicators/migrations/0004_alter_indicator_base.py
new file mode 100644
index 0000000..b01df46
--- /dev/null
+++ b/src/indicators/migrations/0004_alter_indicator_base.py
@@ -0,0 +1,19 @@
+# Generated by Django 5.0.7 on 2025-05-05 16:22
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('indicators', '0003_alter_indicator_geographic_scope_and_more'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='indicator',
+            name='base',
+            field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='base_for', to='indicators.indicator', verbose_name='Base Indicator'),
+        ),
+    ]
diff --git a/src/indicators/models.py b/src/indicators/models.py
index 3279652..ca7ed2e 100644
--- a/src/indicators/models.py
+++ b/src/indicators/models.py
@@ -367,7 +367,7 @@ class Indicator(models.Model):
         "indicators.Indicator",
         verbose_name="Base Indicator",
         related_name="base_for",
-        on_delete=models.PROTECT,
+        on_delete=models.CASCADE,
         null=True,
         blank=True,
     )
diff --git a/src/indicatorsets/filters.py b/src/indicatorsets/filters.py
index e98d511..dd82525 100644
--- a/src/indicatorsets/filters.py
+++ b/src/indicatorsets/filters.py
@@ -7,24 +7,16 @@
 
 
 from indicatorsets.models import IndicatorSet
-from indicatorsets.utils import get_list_of_indicators_filtered_by_geo
+from indicatorsets.utils import (
+    get_list_of_indicators_filtered_by_geo,
+    get_original_data_provider_choices,
+)
 from indicators.models import Indicator
 from base.models import Pathogen, GeographicScope, Geography, SeverityPyramidRung
 
 
 logger = logging.getLogger(__name__)
 
-try:
-    ORIGINAL_DATA_PROVIDER_CHOICES = [
-        (el, el)
-        for el in set(
-            IndicatorSet.objects.values_list("original_data_provider", flat=True)
-        )
-    ]
-except Exception as e:
-    ORIGINAL_DATA_PROVIDER_CHOICES = [("", "No original data provider available")]
-    print(f"Error fetching original data provider choices: {e}")
-
 
 class IndicatorSetFilter(django_filters.FilterSet):
 
@@ -60,7 +52,7 @@ class IndicatorSetFilter(django_filters.FilterSet):
 
     original_data_provider = django_filters.MultipleChoiceFilter(
         field_name="original_data_provider",
-        choices=ORIGINAL_DATA_PROVIDER_CHOICES,
+        choices=get_original_data_provider_choices,
         widget=QueryArrayWidget,
         lookup_expr="exact",
         required=False,
diff --git a/src/indicatorsets/forms.py b/src/indicatorsets/forms.py
index 11e0813..abf0b8b 100644
--- a/src/indicatorsets/forms.py
+++ b/src/indicatorsets/forms.py
@@ -2,18 +2,7 @@
 
 from base.models import Pathogen, GeographicScope, Geography, SeverityPyramidRung
 from indicatorsets.models import IndicatorSet
-
-
-try:
-    ORIGINAL_DATA_PROVIDER_CHOICES = [
-        (el, el)
-        for el in set(
-            IndicatorSet.objects.values_list("original_data_provider", flat=True)
-        )
-    ]
-except Exception as e:
-    ORIGINAL_DATA_PROVIDER_CHOICES = [("", "No original data provider available")]
-    print(f"Error fetching original data provider choices: {e}")
+from indicatorsets.utils import get_original_data_provider_choices
 
 
 class IndicatorSetFilterForm(forms.ModelForm):
@@ -44,7 +33,7 @@ class IndicatorSetFilterForm(forms.ModelForm):
     )
 
     original_data_provider = forms.ChoiceField(
-        choices=ORIGINAL_DATA_PROVIDER_CHOICES,
+        choices=get_original_data_provider_choices,
         widget=forms.CheckboxSelectMultiple(),
     )
 
diff --git a/src/indicatorsets/utils.py b/src/indicatorsets/utils.py
index daeb7ae..1bf84f0 100644
--- a/src/indicatorsets/utils.py
+++ b/src/indicatorsets/utils.py
@@ -5,6 +5,7 @@
 import requests
 from django.conf import settings
 from epiweeks import Week
+from indicatorsets.models import IndicatorSet
 
 
 def list_to_dict(lst):
@@ -53,3 +54,12 @@ def get_epiweek(start_date, end_date):
     end_date = Week.fromdate(end_date)
     end_date = f"{end_date.year}{end_date.week if end_date.week >= 10 else '0' + str(end_date.week)}"
     return [start_date, end_date]
+
+
+def get_original_data_provider_choices():
+    return [
+        (el, el)
+        for el in IndicatorSet.objects.values_list("original_data_provider", flat=True)
+        .order_by("original_data_provider")
+        .distinct()
+    ]
diff --git a/src/templates/http_errors/400.html b/src/templates/http_errors/400.html
index 26d9026..cac38d2 100644
--- a/src/templates/http_errors/400.html
+++ b/src/templates/http_errors/400.html
@@ -8,7 +8,7 @@
     <section class="section error-404 min-vh-100 d-flex flex-column align-items-center justify-content-center">
       <h1>400</h1>
       <h2>Sorry, the request could not be understood by the server due to malformed syntax.</h2>
-      <a class="btn" href="{% url 'signals' %}">Back to home</a>
+      <a class="btn" href="{% url 'indicatorsets' %}">Back to home</a>
     </section>
 
   </div>
diff --git a/src/templates/http_errors/403.html b/src/templates/http_errors/403.html
index a63efc3..21b8ec9 100644
--- a/src/templates/http_errors/403.html
+++ b/src/templates/http_errors/403.html
@@ -7,7 +7,7 @@
     <section class="section error-404 min-vh-100 d-flex flex-column align-items-center justify-content-center">
       <h1>403</h1>
       <h2>You don't have permission to access this resource.</h2>
-      <a class="btn" href="{% url 'signals' %}">Back to home</a>
+      <a class="btn" href="{% url 'indicatorsets' %}">Back to home</a>
     </section>
   </div>
 {% endblock %}
\ No newline at end of file
diff --git a/src/templates/http_errors/404.html b/src/templates/http_errors/404.html
index 796d499..ae3f65e 100644
--- a/src/templates/http_errors/404.html
+++ b/src/templates/http_errors/404.html
@@ -9,7 +9,7 @@
     <section class="section error-404 min-vh-100 d-flex flex-column align-items-center justify-content-center">
       <h1>404</h1>
       <h2>Not Found</h2>
-      <a class="btn" href="{% url 'signals' %}">Back to home</a>
+      <a class="btn" href="{% url 'indicatorsets' %}">Back to home</a>
     </section>
   </div>
 {% endblock %}
diff --git a/src/templates/http_errors/500.html b/src/templates/http_errors/500.html
index 5cd1b2e..ddf0308 100644
--- a/src/templates/http_errors/500.html
+++ b/src/templates/http_errors/500.html
@@ -7,7 +7,7 @@
     <section class="section error-404 min-vh-100 d-flex flex-column align-items-center justify-content-center">
       <h1>500</h1>
       <h2>Internal Server Error.</h2>
-      <a class="btn" href="{% url 'signals' %}">Back to home</a>
+      <a class="btn" href="{% url 'indicatorsets' %}">Back to home</a>
     </section>
   </div>
 {% endblock %}
\ No newline at end of file