diff --git a/Controller/ApiController.php b/Controller/ApiController.php
index 1e233ce..a4d688d 100644
--- a/Controller/ApiController.php
+++ b/Controller/ApiController.php
@@ -14,13 +14,14 @@ declare(strict_types=1);
 
 namespace Modules\Tasks\Controller;
 
+use Modules\Admin\Models\NullAccount;
 use Modules\Tasks\Models\Task;
 use Modules\Tasks\Models\TaskElement;
 use Modules\Tasks\Models\TaskElementMapper;
 use Modules\Tasks\Models\TaskMapper;
 use Modules\Tasks\Models\TaskStatus;
-use Modules\Tasks\Models\TaskType;
 
+use Modules\Tasks\Models\TaskType;
 use phpOMS\Message\NotificationLevel;
 use phpOMS\Message\RequestAbstract;
 use phpOMS\Message\ResponseAbstract;
@@ -117,7 +118,7 @@ final class ApiController extends Controller
         $task->setTitle((string) ($request->getData('title') ?? ''));
         $task->setDescription(Markdown::parse((string) ($request->getData('plain') ?? '')));
         $task->setDescriptionRaw((string) ($request->getData('plain') ?? ''));
-        $task->setCreatedBy($request->getHeader()->getAccount());
+        $task->setCreatedBy(new NullAccount($request->getHeader()->getAccount()));
         $task->setDue(new \DateTime($request->getData('due')));
         $task->setStatus(TaskStatus::OPEN);
         $task->setType(TaskType::SINGLE);
@@ -269,7 +270,7 @@ final class ApiController extends Controller
     private function createTaskElementFromRequest(RequestAbstract $request) : TaskElement
     {
         $element = new TaskElement();
-        $element->setCreatedBy($request->getHeader()->getAccount());
+        $element->setCreatedBy(new NullAccount($request->getHeader()->getAccount()));
         $element->setDue(new \DateTime((string) ($request->getData('due') ?? 'now')));
         $element->setPriority((int) $request->getData('priority'));
         $element->setStatus((int) ($request->getData('status')));
diff --git a/Models/NullTask.php b/Models/NullTask.php
index ff72358..e57ca77 100644
--- a/Models/NullTask.php
+++ b/Models/NullTask.php
@@ -24,4 +24,15 @@ namespace Modules\Tasks\Models;
  */
 final class NullTask extends Task
 {
+    /**
+     * Constructor
+     *
+     * @param int $id Model id
+     *
+     * @since 1.0.0
+     */
+    public function __construct(int $id = 0)
+    {
+        $this->id = $id;
+    }
 }
diff --git a/Models/Task.php b/Models/Task.php
index b7d523e..8b145c0 100644
--- a/Models/Task.php
+++ b/Models/Task.php
@@ -14,7 +14,10 @@ declare(strict_types=1);
 
 namespace Modules\Tasks\Models;
 
+use Modules\Admin\Models\Account;
+use Modules\Admin\Models\NullAccount;
 use Modules\Calendar\Models\Schedule;
+use Modules\Media\Models\Media;
 use Modules\Tag\Models\NullTag;
 use Modules\Tag\Models\Tag;
 use phpOMS\Stdlib\Base\Exception\InvalidEnumValue;
@@ -51,7 +54,7 @@ class Task implements \JsonSerializable
      * @var int
      * @since 1.0.0
      */
-    protected $createdBy = 0;
+    protected Account $createdBy;
 
     /**
      * Created.
@@ -115,7 +118,7 @@ class Task implements \JsonSerializable
      * @var null|\DateTime
      * @since 1.0.0
      */
-    protected $start = null;
+    protected ?\DateTime $start = null;
 
     /**
      * Due.
@@ -123,7 +126,7 @@ class Task implements \JsonSerializable
      * @var null|\DateTime
      * @since 1.0.0
      */
-    protected $due = null;
+    protected ?\DateTime $due = null;
 
     /**
      * Done.
@@ -131,7 +134,7 @@ class Task implements \JsonSerializable
      * @var null|\DateTime
      * @since 1.0.0
      */
-    protected $done = null;
+    protected ?\DateTime $done = null;
 
     /**
      * Task elements.
@@ -155,7 +158,7 @@ class Task implements \JsonSerializable
      * @var Schedule
      * @since 1.0.0
      */
-    protected $schedule = null;
+    protected Schedule $schedule;
 
     /**
      * Priority
@@ -180,6 +183,7 @@ class Task implements \JsonSerializable
      */
     public function __construct()
     {
+        $this->createdBy = new NullAccount();
         $this->createdAt = new \DateTime('now');
         $this->schedule  = new Schedule();
         $this->start     = new \DateTime('now');
@@ -298,7 +302,7 @@ class Task implements \JsonSerializable
     /**
      * Get all media
      *
-     * @return array<int|\Modules\Media\Models\Media>
+     * @return Media[]
      *
      * @since 1.0.0
      */
@@ -310,13 +314,13 @@ class Task implements \JsonSerializable
     /**
      * Add media
      *
-     * @param mixed $media Media to add
+     * @param Media $media Media to add
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function addMedia($media) : void
+    public function addMedia(Media $media) : void
     {
         $this->media[] = $media;
     }
@@ -408,7 +412,7 @@ class Task implements \JsonSerializable
      */
     public function getCreatedAt() : \DateTime
     {
-        return $this->createdAt ?? new \DateTime();
+        return $this->createdAt;
     }
 
     /**
@@ -438,11 +442,11 @@ class Task implements \JsonSerializable
     /**
      * Get created by
      *
-     * @return int|\phpOMS\Account\Account
+     * @return Account
      *
      * @since 1.0.0
      */
-    public function getCreatedBy()
+    public function getCreatedBy() : Account
     {
         return $this->createdBy;
     }
@@ -450,16 +454,16 @@ class Task implements \JsonSerializable
     /**
      * Set created by
      *
-     * @param mixed $id Created by
+     * @param Account $account Created by
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function setCreatedBy($id) : void
+    public function setCreatedBy(Account $account) : void
     {
-        $this->createdBy = $id;
-        $this->schedule->setCreatedBy($id);
+        $this->createdBy = $account;
+        $this->schedule->setCreatedBy($account);
     }
 
     /**
diff --git a/Models/TaskElement.php b/Models/TaskElement.php
index 1907292..ba4dc25 100644
--- a/Models/TaskElement.php
+++ b/Models/TaskElement.php
@@ -16,7 +16,8 @@ namespace Modules\Tasks\Models;
 
 use Modules\Admin\Models\Account;
 use Modules\Admin\Models\Group;
-
+use Modules\Admin\Models\NullAccount;
+use Modules\Media\Models\Media;
 use phpOMS\Stdlib\Base\Exception\InvalidEnumValue;
 
 /**
@@ -64,10 +65,10 @@ class TaskElement implements \JsonSerializable
     /**
      * Creator.
      *
-     * @var int|\Modules\Admin\Models\Account
+     * @var Account
      * @since 1.0.0
      */
-    private $createdBy = 0;
+    private Account $createdBy;
 
     /**
      * Created.
@@ -104,7 +105,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Media.
      *
-     * @var array
+     * @var Media[]
      * @since 1.0.0
      */
     private array $media = [];
@@ -112,7 +113,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Accounts who received this task element.
      *
-     * @var array
+     * @var AccountRelation[]
      * @since 1.0.0
      */
     protected array $accRelation = [];
@@ -120,7 +121,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Groups who received this task element.
      *
-     * @var array
+     * @var GroupRelaction[]
      * @since 1.0.0
      */
     protected array $grpRelation = [];
@@ -135,6 +136,7 @@ class TaskElement implements \JsonSerializable
         $this->due = new \DateTime('now');
         $this->due->modify('+1 day');
         $this->createdAt = new \DateTime('now');
+        $this->createdBy = new NullAccount();
     }
 
     /**
@@ -160,11 +162,11 @@ class TaskElement implements \JsonSerializable
     }
 
     /**
-     * @return int|\phpOMS\Account\Account
+     * @return Account
      *
      * @since 1.0.0
      */
-    public function getCreatedBy()
+    public function getCreatedBy() : Account
     {
         return $this->createdBy;
     }
@@ -172,13 +174,13 @@ class TaskElement implements \JsonSerializable
     /**
      * Set created by
      *
-     * @param mixed $creator Creator
+     * @param Account $creator Creator
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function setCreatedBy($creator) : void
+    public function setCreatedBy(Account $creator) : void
     {
         $this->createdBy = $creator;
     }
@@ -186,7 +188,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Get all media
      *
-     * @return array
+     * @return Media[]
      *
      * @since 1.0.0
      */
@@ -198,13 +200,13 @@ class TaskElement implements \JsonSerializable
     /**
      * Add media
      *
-     * @param mixed $media Media to add
+     * @param Media $media Media to add
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function addMedia($media) : void
+    public function addMedia(Media $media) : void
     {
         $this->media[] = $media;
     }
@@ -321,7 +323,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Get to
      *
-     * @return array<RelationAbstract>
+     * @return RelationAbstract[]
      *
      * @since 1.0.0
      */
@@ -443,7 +445,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Add to
      *
-     * @param mixed $to To
+     * @param Group|Account $to To
      *
      * @return void
      *
@@ -453,7 +455,7 @@ class TaskElement implements \JsonSerializable
     {
         if ($to instanceof Group) {
             $this->addGroupTo($to);
-        } elseif (($to instanceof Account) || \is_int($to)) {
+        } elseif (($to instanceof Account)) {
             $this->addAccountTo($to);
         }
     }
@@ -461,15 +463,15 @@ class TaskElement implements \JsonSerializable
     /**
      * Add group as to
      *
-     * @param int|Group $group Group
+     * @param Group $group Group
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function addGroupTo($group) : void
+    public function addGroupTo(Group $group) : void
     {
-        $groupId = \is_int($group) ? $group : $group->getId();
+        $groupId = $group->getId();
 
         foreach ($this->grpRelation as $grp) {
             $grpId = !\is_int($grp->getRelation()) ? $grp->getRelation()->getId() : $grp->getRelation();
@@ -485,15 +487,15 @@ class TaskElement implements \JsonSerializable
     /**
      * Add account as to
      *
-     * @param int|Account $account Account
+     * @param Account $account Account
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function addAccountTo($account) : void
+    public function addAccountTo(Account $account) : void
     {
-        $accountId = \is_int($account) ? $account : $account->getId();
+        $accountId = $account->getId();
 
         foreach ($this->accRelation as $acc) {
             $accId = !\is_int($acc->getRelation()) ? $acc->getRelation()->getId() : $acc->getRelation();
@@ -509,7 +511,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Get cc
      *
-     * @return array<RelationAbstract>
+     * @return RelationAbstract[]
      *
      * @since 1.0.0
      */
@@ -535,7 +537,7 @@ class TaskElement implements \JsonSerializable
     /**
      * Add cc
      *
-     * @param mixed $cc CC
+     * @param Group|Account $cc CC
      *
      * @return void
      *
@@ -545,7 +547,7 @@ class TaskElement implements \JsonSerializable
     {
         if ($cc instanceof Group) {
             $this->addGroupCC($cc);
-        } elseif (($cc instanceof Account) || \is_int($cc)) {
+        } elseif (($cc instanceof Account)) {
             $this->addAccountCC($cc);
         }
     }
@@ -553,15 +555,15 @@ class TaskElement implements \JsonSerializable
     /**
      * Add group as cc
      *
-     * @param int|Group $group Group
+     * @param Group $group Group
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function addGroupCC($group) : void
+    public function addGroupCC(Group $group) : void
     {
-        $groupId = \is_int($group) ? $group : $group->getId();
+        $groupId = $group->getId();
 
         foreach ($this->grpRelation as $grp) {
             $grpId = !\is_int($grp->getRelation()) ? $grp->getRelation()->getId() : $grp->getRelation();
@@ -577,15 +579,15 @@ class TaskElement implements \JsonSerializable
     /**
      * Add account as cc
      *
-     * @param int|Account $account Account
+     * @param Account $account Account
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function addAccountCC($account) : void
+    public function addAccountCC(Account $account) : void
     {
-        $accountId = \is_int($account) ? $account : $account->getId();
+        $accountId = $account->getId();
 
         foreach ($this->accRelation as $acc) {
             $accId = !\is_int($acc->getRelation()) ? $acc->getRelation()->getId() : $acc->getRelation();
diff --git a/Models/TaskElementMapper.php b/Models/TaskElementMapper.php
index 0481a1e..5f22ad5 100644
--- a/Models/TaskElementMapper.php
+++ b/Models/TaskElementMapper.php
@@ -42,7 +42,7 @@ final class TaskElementMapper extends DataMapperAbstract
         'task_element_priority'   => ['name' => 'task_element_priority',   'type' => 'int',      'internal' => 'priority'],
         'task_element_due'        => ['name' => 'task_element_due',        'type' => 'DateTime', 'internal' => 'due'],
         'task_element_task'       => ['name' => 'task_element_task',       'type' => 'int',      'internal' => 'task'],
-        'task_element_created_by' => ['name' => 'task_element_created_by', 'type' => 'int',      'internal' => 'createdBy'],
+        'task_element_created_by' => ['name' => 'task_element_created_by', 'type' => 'int',      'internal' => 'createdBy', 'readonly' => true],
         'task_element_created_at' => ['name' => 'task_element_created_at', 'type' => 'DateTime', 'internal' => 'createdAt', 'readonly' => true],
     ];
 
diff --git a/Models/TaskMapper.php b/Models/TaskMapper.php
index f72aa63..8e13139 100644
--- a/Models/TaskMapper.php
+++ b/Models/TaskMapper.php
@@ -50,7 +50,7 @@ final class TaskMapper extends DataMapperAbstract
         'task_done'       => ['name' => 'task_done',       'type' => 'DateTime', 'internal' => 'done'],
         'task_schedule'   => ['name' => 'task_schedule',   'type' => 'int',      'internal' => 'schedule'],
         'task_start'      => ['name' => 'task_start',      'type' => 'DateTime', 'internal' => 'start'],
-        'task_created_by' => ['name' => 'task_created_by', 'type' => 'int',      'internal' => 'createdBy'],
+        'task_created_by' => ['name' => 'task_created_by', 'type' => 'int',      'internal' => 'createdBy', 'readonly' => true],
         'task_created_at' => ['name' => 'task_created_at', 'type' => 'DateTime', 'internal' => 'createdAt', 'readonly' => true],
     ];
 
@@ -325,6 +325,8 @@ final class TaskMapper extends DataMapperAbstract
                 ->where(self::$table . '.task_status', '=', TaskStatus::OPEN)
                 ->andWhere(AccountRelationMapper::getTable() . '.task_account_account', '=', $user);
 
+            $t = $query->toSql();
+
             $sth = self::$db->con->prepare($query->toSql());
             $sth->execute();