diff --git a/tests/base.py b/tests/base.py
index c81ac7d3d6..bbf4d366fd 100755
--- a/tests/base.py
+++ b/tests/base.py
@@ -1300,11 +1300,12 @@ class ZuulTestCase(BaseTestCase):
             self.config, self.sched)
         self.nodepool = zuul.nodepool.Nodepool(self.sched)
         self.zk = zuul.zk.ZooKeeper()
-        self.zk.connect([self.zk_config])
+        self.zk.connect(self.zk_config)
 
-        self.fake_nodepool = FakeNodepool(self.zk_config.host,
-                                          self.zk_config.port,
-                                          self.zk_config.chroot)
+        self.fake_nodepool = FakeNodepool(
+            self.zk_chroot_fixture.zookeeper_host,
+            self.zk_chroot_fixture.zookeeper_port,
+            self.zk_chroot_fixture.zookeeper_chroot)
 
         self.sched.setLauncher(self.launch_client)
         self.sched.setMerger(self.merge_client)
@@ -1380,7 +1381,7 @@ class ZuulTestCase(BaseTestCase):
 
     def setupZK(self):
         self.zk_chroot_fixture = self.useFixture(ChrootedKazooFixture())
-        self.zk_config = zuul.zk.ZooKeeperConnectionConfig(
+        self.zk_config = '%s:%s%s' % (
             self.zk_chroot_fixture.zookeeper_host,
             self.zk_chroot_fixture.zookeeper_port,
             self.zk_chroot_fixture.zookeeper_chroot)
diff --git a/tests/unit/test_nodepool.py b/tests/unit/test_nodepool.py
index 6462f9af98..19c7e05bf4 100644
--- a/tests/unit/test_nodepool.py
+++ b/tests/unit/test_nodepool.py
@@ -30,22 +30,23 @@ class TestNodepool(BaseTestCase):
         super(BaseTestCase, self).setUp()
 
         self.zk_chroot_fixture = self.useFixture(ChrootedKazooFixture())
-        self.zk_config = zuul.zk.ZooKeeperConnectionConfig(
+        self.zk_config = '%s:%s%s' % (
             self.zk_chroot_fixture.zookeeper_host,
             self.zk_chroot_fixture.zookeeper_port,
             self.zk_chroot_fixture.zookeeper_chroot)
 
         self.zk = zuul.zk.ZooKeeper()
-        self.zk.connect([self.zk_config])
+        self.zk.connect(self.zk_config)
 
         self.provisioned_requests = []
         # This class implements the scheduler methods zuul.nodepool
         # needs, so we pass 'self' as the scheduler.
         self.nodepool = zuul.nodepool.Nodepool(self)
 
-        self.fake_nodepool = FakeNodepool(self.zk_config.host,
-                                          self.zk_config.port,
-                                          self.zk_config.chroot)
+        self.fake_nodepool = FakeNodepool(
+            self.zk_chroot_fixture.zookeeper_host,
+            self.zk_chroot_fixture.zookeeper_port,
+            self.zk_chroot_fixture.zookeeper_chroot)
 
     def waitForRequests(self):
         # Wait until all requests are complete.
diff --git a/zuul/zk.py b/zuul/zk.py
index a4568738fa..2009945b86 100644
--- a/zuul/zk.py
+++ b/zuul/zk.py
@@ -64,23 +64,6 @@ class ZooKeeperConnectionConfig(object):
         self.chroot = chroot or ''
 
 
-def buildZooKeeperHosts(host_list):
-    '''
-    Build the ZK cluster host list for client connections.
-
-    :param list host_list: A list of
-        :py:class:`~nodepool.zk.ZooKeeperConnectionConfig` objects (one
-        per server) defining the ZooKeeper cluster servers.
-    '''
-    if not isinstance(host_list, list):
-        raise Exception("'host_list' must be a list")
-    hosts = []
-    for host_def in host_list:
-        host = '%s:%s%s' % (host_def.host, host_def.port, host_def.chroot)
-        hosts.append(host)
-    return ",".join(hosts)
-
-
 class ZooKeeper(object):
     '''
     Class implementing the ZooKeeper interface.
@@ -158,8 +141,7 @@ class ZooKeeper(object):
 
         '''
         if self.client is None:
-            hosts = buildZooKeeperHosts(host_list)
-            self.client = KazooClient(hosts=hosts, read_only=read_only)
+            self.client = KazooClient(hosts=host_list, read_only=read_only)
             self.client.add_listener(self._connection_listener)
             self.client.start()
 
@@ -184,8 +166,7 @@ class ZooKeeper(object):
             (one per server) defining the ZooKeeper cluster servers.
         '''
         if self.client is not None:
-            hosts = buildZooKeeperHosts(host_list)
-            self.client.set_hosts(hosts=hosts)
+            self.client.set_hosts(hosts=host_list)
 
     def submitNodeRequest(self, node_request, watcher):
         '''