diff --git a/gusto/limiters.py b/gusto/limiters.py
index 2011bc680..41adde50d 100644
--- a/gusto/limiters.py
+++ b/gusto/limiters.py
@@ -181,7 +181,7 @@ def apply(self, field):
 
 
 class MixedFSLimiter(object):
-    """An object to hold a dictionary that defines limiters for transported prognostic 
+    """An object to hold a dictionary that defines limiters for transported prognostic
     variables. Different limiters may be applied to different fields and not every transported variable needs a defined limiter.
     """