diff --git a/r2/r2/controllers/multi.py b/r2/r2/controllers/multi.py
index 07949feee..e48fa057b 100644
--- a/r2/r2/controllers/multi.py
+++ b/r2/r2/controllers/multi.py
@@ -140,7 +140,7 @@ class MultiApiController(RedditController, OAuth2ResourceController):
         """Add a subreddit to a multi."""
 
         try:
-            multi.add_srs({sr._id: {}})
+            multi.add_srs({sr: {}})
         except TooManySubredditsException as e:
             raise RedditError('MULTI_TOO_MANY_SUBREDDITS', code=409)
         else:
@@ -156,5 +156,5 @@ class MultiApiController(RedditController, OAuth2ResourceController):
     )
     def DELETE_multi_subreddit(self, multi, sr):
         """Remove a subreddit from a multi."""
-        multi.del_srs(sr._id)
+        multi.del_srs(sr)
         multi._commit()
diff --git a/r2/r2/models/subreddit.py b/r2/r2/models/subreddit.py
index a87bba2eb..a012def52 100644
--- a/r2/r2/models/subreddit.py
+++ b/r2/r2/models/subreddit.py
@@ -1416,9 +1416,12 @@ class LabeledMulti(tdb_cassandra.Thing, MultiReddit):
 
     @classmethod
     def sr_props_to_columns(cls, sr_props):
-        sr_columns = {cls.SR_PREFIX + str(sr_id): json.dumps(props)
-                      for sr_id, props in sr_props.iteritems()}
-        return sr_columns
+        columns = {}
+        for sr_id, props in sr_props.iteritems():
+            if isinstance(sr_id, Subreddit):
+                sr_id = sr_id._id
+            columns[cls.SR_PREFIX + str(sr_id)] = json.dumps(props)
+        return columns
 
     @classmethod
     def columns_to_sr_props(cls, columns):