diff --git a/src/EcsWorld.cs b/src/EcsWorld.cs
index dc4e0ef..40a345a 100644
--- a/src/EcsWorld.cs
+++ b/src/EcsWorld.cs
@@ -274,7 +274,6 @@ namespace DCFApixels.DragonECS
 
         public void DeleteEmptyEntites()
         {
-            throw new NotImplementedException();
             foreach (var e in Entities)
             {
                 if (_componentCounts[e] <= 0)
diff --git a/src/EcsWorld.pools.cs b/src/EcsWorld.pools.cs
index c790a83..71ef175 100644
--- a/src/EcsWorld.pools.cs
+++ b/src/EcsWorld.pools.cs
@@ -142,15 +142,17 @@ namespace DCFApixels.DragonECS
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private void UnregisterEntityComponent(int entityID, int componentTypeID, EcsMaskChunck maskBit)
         {
-//            _poolComponentCounts[componentTypeID]--;
-//            var count = --_componentCounts[entityID];
-//            _entitiesComponentMasks[entityID][maskBit.chankIndex] &= ~maskBit.mask;
-//
-//            if (count == 0 && _allEntites.Has(entityID))
-//                DelEntity(entityID);
-//#if (DEBUG && !DISABLE_DEBUG) || ENABLE_DRAGONECS_ASSERT_CHEKS
-//            if (count < 0) Throw.World_InvalidIncrementComponentsBalance();
-//#endif
+            _poolComponentCounts[componentTypeID]--;
+            var count = --_componentCounts[entityID];
+            _entitiesComponentMasks[entityID][maskBit.chankIndex] &= ~maskBit.mask;
+
+            if (count == 0 && IsUsed(entityID))
+            {
+                DelEntity(entityID);
+            }
+#if (DEBUG && !DISABLE_DEBUG) || ENABLE_DRAGONECS_ASSERT_CHEKS
+            if (count < 0) Throw.World_InvalidIncrementComponentsBalance();
+#endif
         }
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private bool HasEntityComponent(int entityID, EcsMaskChunck maskBit)