diff --git a/app/assets/javascripts/discourse/app/components/edit-category-settings.hbs b/app/assets/javascripts/discourse/app/components/edit-category-settings.hbs
index 2a36e0531d..cd027fcb60 100644
--- a/app/assets/javascripts/discourse/app/components/edit-category-settings.hbs
+++ b/app/assets/javascripts/discourse/app/components/edit-category-settings.hbs
@@ -187,7 +187,7 @@
       {{i18n "category.num_auto_bump_daily"}}
     </label>
     <NumberField
-      @number={{this.category.custom_fields.num_auto_bump_daily}}
+      @number={{this.category.category_setting.num_auto_bump_daily}}
       @id="category-number-daily-bump"
       @type="number"
       @min="0"
diff --git a/app/controllers/categories_controller.rb b/app/controllers/categories_controller.rb
index 0bf524f965..07e7b35a2f 100644
--- a/app/controllers/categories_controller.rb
+++ b/app/controllers/categories_controller.rb
@@ -406,7 +406,7 @@ class CategoriesController < ApplicationController
             :read_only_banner,
             :default_list_filter,
             :reviewable_by_group_id,
-            category_setting_attributes: %i[auto_bump_cooldown_days],
+            category_setting_attributes: %i[auto_bump_cooldown_days num_auto_bump_daily],
             custom_fields: [custom_field_params],
             permissions: [*p.try(:keys)],
             allowed_tags: [],
diff --git a/app/models/category.rb b/app/models/category.rb
index 23aab1c218..427dbc3fe6 100644
--- a/app/models/category.rb
+++ b/app/models/category.rb
@@ -18,11 +18,9 @@ class Category < ActiveRecord::Base
 
   REQUIRE_TOPIC_APPROVAL = "require_topic_approval"
   REQUIRE_REPLY_APPROVAL = "require_reply_approval"
-  NUM_AUTO_BUMP_DAILY = "num_auto_bump_daily"
 
   register_custom_field_type(REQUIRE_TOPIC_APPROVAL, :boolean)
   register_custom_field_type(REQUIRE_REPLY_APPROVAL, :boolean)
-  register_custom_field_type(NUM_AUTO_BUMP_DAILY, :integer)
 
   belongs_to :topic
   belongs_to :topic_only_relative_url,
@@ -48,7 +46,11 @@ class Category < ActiveRecord::Base
 
   has_one :category_setting, dependent: :destroy
 
-  delegate :auto_bump_cooldown_days, to: :category_setting, allow_nil: true
+  delegate :auto_bump_cooldown_days,
+           :num_auto_bump_daily,
+           :num_auto_bump_daily=,
+           to: :category_setting,
+           allow_nil: true
 
   has_and_belongs_to_many :web_hooks
 
@@ -629,14 +631,6 @@ class Category < ActiveRecord::Base
     custom_fields[REQUIRE_REPLY_APPROVAL]
   end
 
-  def num_auto_bump_daily
-    custom_fields[NUM_AUTO_BUMP_DAILY]
-  end
-
-  def num_auto_bump_daily=(v)
-    custom_fields[NUM_AUTO_BUMP_DAILY] = v
-  end
-
   def auto_bump_limiter
     return nil if num_auto_bump_daily.to_i == 0
     RateLimiter.new(nil, "auto_bump_limit_#{self.id}", 1, 86_400 / num_auto_bump_daily.to_i)
@@ -647,13 +641,11 @@ class Category < ActiveRecord::Base
   end
 
   def self.auto_bump_topic!
-    auto_bumps =
-      CategoryCustomField
-        .where(name: Category::NUM_AUTO_BUMP_DAILY)
-        .where('NULLIF(value, \'\')::int > 0')
-        .select(:category_id)
-
-    Category.where(id: auto_bumps).shuffle.any? { |c| c.auto_bump_topic! }
+    Category
+      .joins(:category_setting)
+      .where("category_settings.num_auto_bump_daily > 0")
+      .shuffle
+      .any? { |c| c.auto_bump_topic! }
   end
 
   # will automatically bump a single topic
diff --git a/spec/models/category_spec.rb b/spec/models/category_spec.rb
index 3157f3e4db..48515c50db 100644
--- a/spec/models/category_spec.rb
+++ b/spec/models/category_spec.rb
@@ -974,10 +974,10 @@ RSpec.describe Category do
       category =
         Fabricate(
           :category_with_definition,
-          num_auto_bump_daily: 2,
           created_at: 1.minute.ago,
           category_setting_attributes: {
             auto_bump_cooldown_days: 1,
+            num_auto_bump_daily: 2,
           },
         )
       category.clear_auto_bump_cache!
diff --git a/spec/requests/categories_controller_spec.rb b/spec/requests/categories_controller_spec.rb
index 863ad47be4..fdcbb19f34 100644
--- a/spec/requests/categories_controller_spec.rb
+++ b/spec/requests/categories_controller_spec.rb
@@ -743,7 +743,6 @@ RSpec.describe CategoriesController do
         it "updates per-category settings correctly" do
           category.custom_fields[Category::REQUIRE_TOPIC_APPROVAL] = false
           category.custom_fields[Category::REQUIRE_REPLY_APPROVAL] = false
-          category.custom_fields[Category::NUM_AUTO_BUMP_DAILY] = 0
 
           category.navigate_to_first_post_after_read = false
           category.save!
@@ -757,6 +756,8 @@ RSpec.describe CategoriesController do
                 custom_fields: {
                   require_reply_approval: true,
                   require_topic_approval: true,
+                },
+                category_setting_attributes: {
                   num_auto_bump_daily: 10,
                 },
               }