diff --git a/pyzebra/anatric.py b/pyzebra/anatric.py
index 60c684d..ddd4e34 100644
--- a/pyzebra/anatric.py
+++ b/pyzebra/anatric.py
@@ -28,10 +28,16 @@ class AnatricConfig:
             self.load_from_file(filename)
 
     def load_from_file(self, filename):
-        tree = ET.parse(filename)
-        self._tree = tree
+        self._tree = ET.parse(filename)
+        self._root = self._tree.getroot()
 
-        alg_elem = tree.find("Algorithm")
+        self._alg_elems = dict()
+        for alg in ALGORITHMS:
+            self._alg_elems[alg] = ET.Element("Algorithm", attrib={"implementation": alg})
+
+        self._alg_elems[self.algorithm] = self._tree.find("Algorithm")
+
+        alg_elem = self._tree.find("Algorithm")
         if self.algorithm == "adaptivemaxcog":
             self.threshold = float(alg_elem.find("threshold").attrib["value"])
             self.shell = float(alg_elem.find("shell").attrib["value"])
@@ -213,7 +219,8 @@ class AnatricConfig:
         if value not in ALGORITHMS:
             raise ValueError("Unknown algorithm.")
 
-        self._tree.find("Algorithm").attrib["implementation"] = value
+        self._root.remove(self._tree.find("Algorithm"))
+        self._root.append(self._alg_elems[value])
 
     def save_as(self, filename):
         self._tree.write(filename)