diff --git a/migrations/005_drop_other_indices.py b/migrations/005_drop_other_indices.py
new file mode 100644
index 0000000000..2f942f7a71
--- /dev/null
+++ b/migrations/005_drop_other_indices.py
@@ -0,0 +1,40 @@
+import peewee as pw
+from peewee_migrate import Migrator
+
+
+def migrate(migrator: Migrator, database: pw.Database, *, fake=False):
+    """Drop unused indices:
+
+    - prediction_data: 6242 MB in prod
+    - prediction_source_image: 1795 MB in prod
+    - product_insight_bounding_box: 188 MB in prod
+    - product_insight_confidence: 332 MB in prod
+    - image_prediction_model_version: 533 MB in prod
+    - product_insight_username: 661 MB in prod
+    """
+    migrator.sql("DROP INDEX IF EXISTS prediction_data")
+    migrator.sql("DROP INDEX IF EXISTS prediction_source_image")
+
+    migrator.sql("DROP INDEX IF EXISTS logo_confidence_threshold_type")
+    migrator.sql("DROP INDEX IF EXISTS logoconfidencethreshold_type")
+
+    migrator.sql("DROP INDEX IF EXISTS logo_confidence_threshold_value")
+    migrator.sql("DROP INDEX IF EXISTS logoconfidencethreshold_value")
+
+    migrator.sql("DROP INDEX IF EXISTS product_insight_bounding_box")
+    migrator.sql("DROP INDEX IF EXISTS productinsight_bounding_box")
+
+    migrator.sql("DROP INDEX IF EXISTS product_insight_confidence")
+    migrator.sql("DROP INDEX IF EXISTS productinsight_confidence")
+
+    migrator.sql("DROP INDEX IF EXISTS image_prediction_model_version")
+    migrator.sql("DROP INDEX IF EXISTS imagepredictionmodel_version")
+
+    migrator.sql("DROP INDEX IF EXISTS product_insight_username")
+    migrator.sql("DROP INDEX IF EXISTS productinsight_username")
+
+
+def rollback(migrator: Migrator, database: pw.Database, *, fake=False):
+    """These indices are too long to build using a migration script, rollback
+    should be done manually."""
+    pass
diff --git a/robotoff/images.py b/robotoff/images.py
index c9016c1176..dd0cd3e607 100644
--- a/robotoff/images.py
+++ b/robotoff/images.py
@@ -264,6 +264,8 @@ def delete_images(product_id: ProductIdentifier, image_ids: list[str]):
         .where(
             Prediction.source_image.in_(source_images),
             Prediction.server_type == server_type,
+            # Add barcode filter to speed up the query
+            Prediction.barcode == product_id.barcode,
         )
         .execute()
     )
@@ -273,6 +275,8 @@ def delete_images(product_id: ProductIdentifier, image_ids: list[str]):
             ProductInsight.source_image.in_(source_images),
             ProductInsight.server_type == server_type,
             ProductInsight.annotation.is_null(),
+            # Add barcode filter to speed up the query
+            ProductInsight.barcode == product_id.barcode,
         )
         .execute()
     )
diff --git a/robotoff/models.py b/robotoff/models.py
index 34204954c9..6c9f2ec713 100644
--- a/robotoff/models.py
+++ b/robotoff/models.py
@@ -130,7 +130,7 @@ class ProductInsight(BaseModel):
 
     # If the insight was annotated manually, this field stores the username of
     # the annotator (or first annotator, if multiple votes were cast).
-    username = peewee.TextField(index=True, null=True)
+    username = peewee.TextField(null=True)
 
     # Stores the list of countries that are associated with the product.
     # E.g. possible values are "en:united-states" or "en:france".
@@ -194,7 +194,7 @@ class ProductInsight(BaseModel):
     # tags
     campaign = BinaryJSONField(null=True, index=True, default=list)
     # Confidence score of the insight, may be null
-    confidence = peewee.FloatField(null=True, index=True)
+    confidence = peewee.FloatField(null=True)
 
     # bounding box corresponding to the area of the image related
     # to the insight that was detected.
@@ -212,11 +212,11 @@ def get_product_id(self) -> ProductIdentifier:
 class Prediction(BaseModel):
     barcode = peewee.CharField(max_length=100, null=False, index=True)
     type = peewee.CharField(max_length=256, index=True)
-    data = BinaryJSONField(index=True)
+    data = BinaryJSONField()
     timestamp = peewee.DateTimeField(index=True)
     value_tag = peewee.TextField(null=True)
     value = peewee.TextField(null=True)
-    source_image = peewee.TextField(null=True, index=True)
+    source_image = peewee.TextField(null=True)
     automatic_processing = peewee.BooleanField(null=True)
     predictor = peewee.CharField(max_length=100, null=True)
     predictor_version = peewee.CharField(max_length=100, null=True)
@@ -392,8 +392,8 @@ class Meta:
 
 
 class LogoConfidenceThreshold(BaseModel):
-    type = peewee.CharField(null=True, index=True)
-    value = peewee.CharField(null=True, index=True)
+    type = peewee.CharField(null=True)
+    value = peewee.CharField(null=True)
     threshold = peewee.FloatField(null=False)