diff --git a/pkg/cluster/cluster_test.go b/pkg/cluster/cluster_test.go
index 9efbc51c6..a1b361642 100644
--- a/pkg/cluster/cluster_test.go
+++ b/pkg/cluster/cluster_test.go
@@ -9,6 +9,7 @@ import (
 	acidv1 "github.com/zalando/postgres-operator/pkg/apis/acid.zalan.do/v1"
 	"github.com/zalando/postgres-operator/pkg/spec"
 	"github.com/zalando/postgres-operator/pkg/util/config"
+	"github.com/zalando/postgres-operator/pkg/util/constants"
 	"github.com/zalando/postgres-operator/pkg/util/k8sutil"
 	"github.com/zalando/postgres-operator/pkg/util/teams"
 	v1 "k8s.io/api/core/v1"
@@ -704,3 +705,20 @@ func TestServiceAnnotations(t *testing.T) {
 		})
 	}
 }
+
+func TestInitSystemUsers(t *testing.T) {
+	testName := "Test system users initialization"
+
+	// default cluster without connection pool
+	cl.initSystemUsers()
+	if _, exist := cl.systemUsers[constants.ConnectionPoolUserKeyName]; exist {
+		t.Errorf("%s, connection pool user is present", testName)
+	}
+
+	// cluster with connection pool
+	cl.Spec.EnableConnectionPool = boolToPointer(true)
+	cl.initSystemUsers()
+	if _, exist := cl.systemUsers[constants.ConnectionPoolUserKeyName]; !exist {
+		t.Errorf("%s, connection pool user is not present", testName)
+	}
+}
diff --git a/pkg/cluster/resources_test.go b/pkg/cluster/resources_test.go
index d0cecf841..f06e96e65 100644
--- a/pkg/cluster/resources_test.go
+++ b/pkg/cluster/resources_test.go
@@ -104,4 +104,24 @@ func TestNeedConnPool(t *testing.T) {
 		t.Errorf("%s: Connection pool is not enabled with flag",
 			testName)
 	}
+
+	cluster.Spec = acidv1.PostgresSpec{
+		EnableConnectionPool: boolToPointer(false),
+		ConnectionPool:       &acidv1.ConnectionPool{},
+	}
+
+	if cluster.needConnectionPool() {
+		t.Errorf("%s: Connection pool is still enabled with flag being false",
+			testName)
+	}
+
+	cluster.Spec = acidv1.PostgresSpec{
+		EnableConnectionPool: boolToPointer(true),
+		ConnectionPool:       &acidv1.ConnectionPool{},
+	}
+
+	if !cluster.needConnectionPool() {
+		t.Errorf("%s: Connection pool is not enabled with flag and full",
+			testName)
+	}
 }
diff --git a/pkg/cluster/sync_test.go b/pkg/cluster/sync_test.go
index 4de75880c..ab58b2074 100644
--- a/pkg/cluster/sync_test.go
+++ b/pkg/cluster/sync_test.go
@@ -9,6 +9,7 @@ import (
 	"github.com/zalando/postgres-operator/pkg/util/k8sutil"
 
 	appsv1 "k8s.io/api/apps/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -41,6 +42,14 @@ func objectsAreSaved(cluster *Cluster, err error) error {
 	return nil
 }
 
+func objectsAreDeleted(cluster *Cluster, err error) error {
+	if cluster.ConnectionPool != nil {
+		return fmt.Errorf("Connection pool was not deleted")
+	}
+
+	return nil
+}
+
 func TestConnPoolSynchronization(t *testing.T) {
 	testName := "Test connection pool synchronization"
 	var cluster = New(
@@ -72,6 +81,13 @@ func TestConnPoolSynchronization(t *testing.T) {
 	clusterMock := *cluster
 	clusterMock.KubeClient = k8sutil.NewMockKubernetesClient()
 
+	clusterDirtyMock := *cluster
+	clusterDirtyMock.KubeClient = k8sutil.NewMockKubernetesClient()
+	clusterDirtyMock.ConnectionPool = &ConnectionPoolObjects{
+		Deployment: &appsv1.Deployment{},
+		Service:    &v1.Service{},
+	}
+
 	tests := []struct {
 		subTest string
 		oldSpec *acidv1.Postgresql
@@ -94,6 +110,43 @@ func TestConnPoolSynchronization(t *testing.T) {
 			cluster: &clusterMissingObjects,
 			check:   objectsAreSaved,
 		},
+		{
+			subTest: "create from scratch",
+			oldSpec: &acidv1.Postgresql{
+				Spec: acidv1.PostgresSpec{},
+			},
+			newSpec: &acidv1.Postgresql{
+				Spec: acidv1.PostgresSpec{
+					ConnectionPool: &acidv1.ConnectionPool{},
+				},
+			},
+			cluster: &clusterMissingObjects,
+			check:   objectsAreSaved,
+		},
+		{
+			subTest: "delete if not needed",
+			oldSpec: &acidv1.Postgresql{
+				Spec: acidv1.PostgresSpec{
+					ConnectionPool: &acidv1.ConnectionPool{},
+				},
+			},
+			newSpec: &acidv1.Postgresql{
+				Spec: acidv1.PostgresSpec{},
+			},
+			cluster: &clusterMock,
+			check:   objectsAreDeleted,
+		},
+		{
+			subTest: "cleanup if still there",
+			oldSpec: &acidv1.Postgresql{
+				Spec: acidv1.PostgresSpec{},
+			},
+			newSpec: &acidv1.Postgresql{
+				Spec: acidv1.PostgresSpec{},
+			},
+			cluster: &clusterDirtyMock,
+			check:   objectsAreDeleted,
+		},
 		{
 			subTest: "update deployment",
 			oldSpec: &acidv1.Postgresql{