diff --git a/ocean_c_lab/__init__.py b/ocean_c_lab/__init__.py
index 44f5727..dd35c69 100644
--- a/ocean_c_lab/__init__.py
+++ b/ocean_c_lab/__init__.py
@@ -6,5 +6,5 @@
     __version__ = '0.0.0'  # pragma: no cover
 
 from .box_models import *
-from co2calc import *
+from .co2calc import *
 from .glodap import open_glodap