diff --git a/aircox/tests/models/test_diffusion.py b/aircox/tests/models/test_diffusion.py
index 26b177b..87cf1ae 100644
--- a/aircox/tests/models/test_diffusion.py
+++ b/aircox/tests/models/test_diffusion.py
@@ -1,19 +1,100 @@
 import pytest
+import random
+import datetime
+from model_bakery import baker
+from django.utils import timezone as tz
+from datetime import timedelta
+from aircox.models import Diffusion
 
 
 class TestDiffusionQuerySet:
+   
     @pytest.mark.django_db
     def test_episode_by_obj(self, episodes):
-        pass
+        key_episode = episodes[1]
+        another_episode = episodes[2]
+        diffusions_with_the_key_episode = baker.make(Diffusion, _quantity=3, episode=key_episode)
+        diffusions_without_the_key_episode = baker.make(Diffusion, _quantity=3, episode=another_episode)
+        result = Diffusion.objects.episode(episode=key_episode)
+
+        for diffusion in diffusions_with_the_key_episode:
+            assert diffusion in result
+        for diffusion in diffusions_without_the_key_episode:
+            assert diffusion not in result
 
     @pytest.mark.django_db
     def test_episode_by_id(self, episodes):
-        pass
+        key_episode = episodes[1]
+        another_episode = episodes[2]
+        diffusions_with_the_key_episode = baker.make(Diffusion, _quantity=3, episode=key_episode)
+        diffusions_without_the_key_episode = baker.make(Diffusion, _quantity=3, episode=another_episode)
+        result = Diffusion.objects.episode(id=key_episode.id)
 
+        for diffusion in diffusions_with_the_key_episode:
+            assert diffusion in result
+        for diffusion in diffusions_without_the_key_episode:
+            assert diffusion not in result
+    
     @pytest.mark.django_db
     def test_on_air(self, episodes):
-        pass
+        for episode in episodes:
+            random_type = random.choice([Diffusion.TYPE_ON_AIR, Diffusion.TYPE_UNCONFIRMED])
+            baker.make(Diffusion, episode=episode, type=random_type)
+        result = Diffusion.objects.on_air()
+        
+        for diffusion in result:
+            assert diffusion.type == Diffusion.TYPE_ON_AIR
+            assert diffusion.type != Diffusion.TYPE_UNCONFIRMED
 
     @pytest.mark.django_db
     def test_now(self, episodes):
-        pass
+        now = tz.now()
+        random_episode = random.choice([episodes[1], episodes[0], episodes[2]])
+        now_diffusion = baker.make(Diffusion, episode=random_episode, start=now-timedelta(minutes=30), end=now+timedelta(minutes=30))
+        after_diffusion = baker.make(Diffusion, episode=random_episode, start=now+timedelta(minutes=30), end=now+timedelta(minutes=60))
+        before_diffusion = baker.make(Diffusion, episode=random_episode, start=now-timedelta(minutes=60), end=now-timedelta(minutes=30))
+        result = Diffusion.objects.now(now=now, order=True)
+
+        assert len(result) == 1
+        assert result[0] == now_diffusion
+        assert result[0].start <= now <= result[0].end
+
+    @pytest.mark.django_db
+    def test_date_without_date_arg(self, episodes):
+        today = datetime.date.today()
+        tomorrow = today + timedelta(days=1)
+        random_episode = random.choice([episodes[1], episodes[0], episodes[2]])
+        second_today_diffusion = baker.make(Diffusion, episode=random_episode, start=tz.datetime.combine(today, datetime.time.min) + timedelta(minutes=30), end=tz.datetime.combine(today, datetime.time.max) + timedelta(minutes=60))
+        first_today_diffusion = baker.make(Diffusion, episode=random_episode, start=tz.datetime.combine(today, datetime.time.min), end=tz.datetime.combine(today, datetime.time.max) + timedelta(minutes=30))
+        another_day_diffusion = baker.make(Diffusion, episode=random_episode, start=tz.datetime.combine(tomorrow, datetime.time.min), end=tz.datetime.combine(tomorrow, datetime.time.max))
+    
+        result = Diffusion.objects.date()
+
+        assert len(result) == 2
+        assert result[0] == first_today_diffusion
+        assert result[1] == second_today_diffusion
+
+    @pytest.mark.django_db
+    def test_date_with_date_arg(self, episodes):
+        today = datetime.date.today()
+        tomorrow = today + timedelta(days=1)
+        random_episode = random.choice([episodes[1], episodes[0], episodes[2]])
+        first_today_diffusion = baker.make(Diffusion, episode=random_episode, start=tz.datetime.combine(today, datetime.time.min)-timedelta(minutes=30), end=tz.datetime.combine(today, datetime.time.min)+timedelta(minutes=30))
+        second_tomorrow_diffusion = baker.make(Diffusion, episode=random_episode, start=tz.datetime.combine(tomorrow, datetime.time.min)+timedelta(minutes=30), end=tz.datetime.combine(tomorrow, datetime.time.min)+timedelta(minutes=60))
+        first_tomorrow_diffusion = baker.make(Diffusion, episode=random_episode, start=tz.datetime.combine(tomorrow, datetime.time.min), end=tz.datetime.combine(tomorrow, datetime.time.min)+timedelta(minutes=60))
+        
+        result = Diffusion.objects.date(date=tomorrow)
+
+        assert len(result) == 2
+        assert result[0] == first_tomorrow_diffusion
+        assert result[1] == second_tomorrow_diffusion
+
+    #@pytest.mark.django_db
+    #def test_at(self, episodes):
+    #    date = datetime.date.today()
+
+
+
+    
+    
+