20w19a

src/main/java/carpet/mixins/SpawnHelperInnerMixin.java

@@ -3,6 +3,7 @@ package carpet.mixins;
 import carpet.fakes.SpawnHelperInnerInterface;
 import carpet.utils.SpawnReporter;
 import it.unimi.dsi.fastutil.objects.Object2IntMap;
+import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
 import net.minecraft.entity.EntityCategory;
 import net.minecraft.util.math.GravityField;
 import net.minecraft.world.SpawnHelper;
@@ -26,7 +27,7 @@ public class SpawnHelperInnerMixin implements SpawnHelperInnerInterface
 
     @Shadow @Final private int spawningChunkCount;
 
-    @Shadow @Final private Object2IntMap<EntityCategory> categoryToCount;
+    @Shadow @Final private Object2IntOpenHashMap<EntityCategory> categoryToCount;
 
     @Shadow @Final private GravityField densityField;
 

src/main/java/carpet/utils/Messenger.java

@@ -112,6 +112,8 @@ public class Messenger
                 return "f";
             case WATER_CREATURE:
                 return "v";
+            case WATER_AMBIENT:
+                return "q";
         }
         return "w";
     }

src/main/java/carpet/utils/SpawnReporter.java

@@ -215,6 +215,8 @@ public class SpawnReporter
                 return EntityCategory.WATER_CREATURE;
             case BROWN:
                 return EntityCategory.AMBIENT;
+            case CYAN:
+                return EntityCategory.WATER_AMBIENT;
         }
         return null;
     }
@@ -233,6 +235,10 @@ public class SpawnReporter
         {
             return EntityCategory.WATER_CREATURE;
         }
+        else if ("fish".equalsIgnoreCase(type_code))
+        {
+            return EntityCategory.WATER_AMBIENT;
+        }
         else if ("ambient".equalsIgnoreCase(type_code))
         {
             return EntityCategory.AMBIENT;