fixes #1815

app/controllers/moderator/post/posts_controller.rb

@@ -13,7 +13,7 @@ module Moderator
         @post = ::Post.find(params[:id])
         if params[:commit] == "Delete"
           @post.flag!(params[:reason])
-          @post.delete!
+          @post.delete!(:reason => params[:reason])
         end
         redirect_to(post_path(@post))
       end

app/models/post.rb

@@ -875,7 +875,11 @@ class Post < ActiveRecord::Base
         update_column(:is_banned, true) if options[:ban] || has_tag?("banned_artist")
 
         unless options[:without_mod_action]
-          ModAction.create(:description => "deleted post ##{id}")
+          if options[:reason]
+            ModAction.create(:description => "deleted post ##{id}, reason: #{options[:reason]}")
+          else
+            ModAction.create(:description => "deleted post ##{id}")
+          end
         end
       end
     end