diff --git a/src/caosdb/apiutils.py b/src/caosdb/apiutils.py
index a8256976b79d71f514fcc1dc9c868f1eeebc76e9..dbab28f963d4d167c4dfc097e25527dfc0baad50 100644
--- a/src/caosdb/apiutils.py
+++ b/src/caosdb/apiutils.py
@@ -381,7 +381,10 @@ def _single_convert_to_python_object(robj, entity):
     return robj
 
 
-def _single_convert_to_entity(entity, robj, **kwargs):
+def _single_convert_to_entity(entity, robj, recursive_depth, **kwargs):
+    """
+    recursive_depth: disabled if 0
+    """
     if robj._id is not None:
         entity.id = robj._id
 
@@ -407,16 +410,16 @@ def _single_convert_to_entity(entity, robj, **kwargs):
             else:
                 entity.add_parent(id=parent)
 
-    def add_property(entity, prop, name, recursive=False, datatype=None):
+    def add_property(entity, prop, name, _recursive=False, datatype=None):
         if datatype is None:
-            raise ArgumentError("datatype must not be None")
+            raise RuntimeError("Datatype must not be None.")
 
         if isinstance(prop, CaosDBPythonEntity):
             entity.add_property(name=name, value=str(
                 prop._id), datatype=datatype)
 
-            if recursive and not prop.do_not_expand:
-                return convert_to_entity(prop, recursive=recursive)
+            if _recursive and not prop.do_not_expand:
+                return convert_to_entity(prop, recursive=_recursive)
             else:
                 return []
         else:
@@ -426,6 +429,11 @@ def _single_convert_to_entity(entity, robj, **kwargs):
 
             return []
 
+    if recursive_depth == 0:
+        recursive = False
+    else:
+        recursive = True
+
     for prop in robj._properties:
         value = robj.__getattribute__(prop)
 
@@ -439,7 +447,7 @@ def _single_convert_to_entity(entity, robj, **kwargs):
 
                         if recursive and not v.do_not_expand:
                             children.append(convert_to_entity(
-                                v, recursive=recursive))
+                                v, recursive=recursive_depth-1))
                     else:
                         if isinstance(v, float) or isinstance(v, int):
                             lst.append(str(v))