diff --git a/app/controllers/api/v1/problems_controller.rb b/app/controllers/api/v1/problems_controller.rb
index 28a0e19..d25e139 100644
--- a/app/controllers/api/v1/problems_controller.rb
+++ b/app/controllers/api/v1/problems_controller.rb
@@ -2,18 +2,21 @@ class Api::V1::ProblemsController < ApplicationController
   respond_to :json, :xml
   
   def index
+    query = {}
+    fields = %w{app_id app_name environment message where first_notice_at last_notice_at resolved resolved_at notices_count}
+    
     if params.key?(:start_date) && params.key?(:end_date)
-      start_date = Date.parse(params[:start_date])
-      end_date = Date.parse(params[:end_date])
-      @problems = Problem.in_date_range(start_date..end_date)
-    else
-      @problems = Problem.all
+      start_date = Time.parse(params[:start_date]).utc
+      end_date = Time.parse(params[:end_date]).utc
+      query = {:first_notice_at=>{"$lte"=>end_date}, "$or"=>[{:resolved_at=>nil}, {:resolved_at=>{"$gte"=>start_date}}]}
     end
     
+    results = benchmark("[api/v1/problems_controller] query time") { Mongoid.master["problems"].find(query, fields: fields).to_a }
+    
     respond_to do |format|
-      format.html { render json: ProblemPresenter.new(@problems) } # render JSON if no extension specified on path
-      format.json { render json: ProblemPresenter.new(@problems) }
-      format.xml  { render xml: ProblemPresenter.new(@problems) }
+      format.html { render json: Yajl.dump(results) } # render JSON if no extension specified on path
+      format.json { render json: Yajl.dump(results) }
+      format.xml  { render xml:  results }
     end
   end
   
diff --git a/app/presenters/problem_presenter.rb b/app/presenters/problem_presenter.rb
deleted file mode 100644
index 412e0f6..0000000
--- a/app/presenters/problem_presenter.rb
+++ /dev/null
@@ -1,42 +0,0 @@
-class ProblemPresenter
-  
-  def initialize(model_or_collection)
-    @model_or_collection = model_or_collection
-  end
-  
-  def to_xml(options={})
-    as_json(options).to_xml(options)
-  end
-  
-  def to_json(options={})
-    Yajl.dump(as_json(options))
-  end
-  
-  def as_json(options={})
-    if collection?
-      @model_or_collection.map { |model| model_as_json(model, options) }
-    else
-      model_as_json(@model_or_collection, options)
-    end
-  end
-  
-  def collection?
-    @model_or_collection.respond_to?(:each)
-  end
-  
-  def model_as_json(problem, options={})
-    {
-      app_id: problem.app_id,
-      app_name: problem.app_name,
-      environment: problem.environment,
-      message: problem.message,
-      where: problem.where,
-      first_notice_at: problem.first_notice_at,
-      last_notice_at: problem.last_notice_at,
-      resolved: problem.resolved,
-      resolved_at: problem.resolved_at,
-      notices_count: problem.notices_count
-    }
-  end
-  
-end
--
libgit2 0.21.2