diff --git a/src/Member.php b/src/Member.php
index 05e9203..b0bd721 100644
--- a/src/Member.php
+++ b/src/Member.php
@@ -38,6 +38,10 @@ class Member extends Model {
         'eintrittsdatum' => 'joined_at',
     ];
 
+    protected $casts = [];
+
+    protected $nullable = ['further_address', 'other_country', 'nickname'];
+
     protected $guarded = [];
 
     public static function fromNami($item) {
@@ -59,7 +63,11 @@ class Member extends Model {
     }
 
     public function getJoinedAtAttribute() {
-        return Carbon::parse($this->attributes['joined_at'])->format('Y-m-d');
+        $date = $this->attributes['joined_at'];
+
+        return empty($date)
+            ? null
+            : Carbon::parse($date)->format('Y-m-d');
     }
 
     public function getGenderIdAttribute() {
@@ -70,4 +78,14 @@ class Member extends Model {
         $this->attributes['gender_id'] = data_get($this->geschlechtMaps, $v, null);
     }
 
+    public function getAttributeValue($key) {
+        $original = parent::getAttributeValue($key);
+
+        if (in_array($key, $this->nullable) && $original === '') {
+            return null;
+        }
+
+        return $original;
+    }
+
 }
diff --git a/tests/Unit/PullMemberTest.php b/tests/Unit/PullMemberTest.php
index c59219f..3ed575c 100644
--- a/tests/Unit/PullMemberTest.php
+++ b/tests/Unit/PullMemberTest.php
@@ -23,7 +23,7 @@ class PullMemberTest extends TestCase
             'other_country' => ['other_country', ['deutsch', null]],
             'address' => ['address', ['straße 1', 'straße 2']],
             'further_address' => ['further_address', ['addrz', null]],
-            'zip' => ['zip', [12345, 5555]],
+            'zip' => ['zip', ['12345', '5555']],
             'location' => ['location', ['SG', 'Köln']],
             'main_phone' => ['main_phone', ['+49888', '+49668']],
             'mobile_phone' => ['mobile_phone', ['+49176', '+49172']],
@@ -35,7 +35,7 @@ class PullMemberTest extends TestCase
             'nationality_id' => ['nationality_id', [1054, null]],
             'confession_id' => ['confession_id', [1, null]],
             'birthday' => ['birthday', ['1991-06-20', '1984-01-17']],
-            'joined_at' => ['joined_at', ['2005-05-01', '2003-11-17']],
+            'joined_at' => ['joined_at', ['2005-05-01', null]],
         ];
     }
 
@@ -53,7 +53,7 @@ class PullMemberTest extends TestCase
             'email_parents' => ['email_parents', ['testp@example.com', 'test2p@example.com']],
             'gender_id' => ['gender_id', [19, null]],
             'birthday' => ['birthday', ['1991-06-20', '1984-01-17']],
-            'joined_at' => ['joined_at', ['2005-05-01', '2003-11-17']],
+            'joined_at' => ['joined_at', ['2005-05-01', null]],
         ];
     }
 
@@ -79,8 +79,8 @@ class PullMemberTest extends TestCase
 
         $group = Nami::group(103);
 
-        $this->assertEquals($values[0], $group->member(16)->{$key});
-        $this->assertEquals($values[1], $group->member(17)->{$key});
+        $this->assertSame($values[0], $group->member(16)->{$key});
+        $this->assertSame($values[1], $group->member(17)->{$key});
 
         Http::assertSentCount(5);
     }
@@ -100,7 +100,7 @@ class PullMemberTest extends TestCase
 
         Nami::login();
 
-        $this->assertEquals([
+        $this->assertSame([
             16 => $values[0],
             17 => $values[1]
         ], Nami::group(103)->members()->pluck($key, 'id')->toArray());
@@ -123,7 +123,7 @@ class PullMemberTest extends TestCase
 
         Nami::login();
 
-        $this->assertEquals([
+        $this->assertSame([
             16 => $values[0],
             17 => $values[1]
         ], Nami::group(103)->members()->pluck($key, 'id')->toArray());
@@ -147,7 +147,7 @@ class PullMemberTest extends TestCase
 
         $group = Nami::group(103);
 
-        $this->assertEquals($values[0], $group->member(16)->{$key});
+        $this->assertSame($values[0], $group->member(16)->{$key});
 
         Http::assertSentCount(5);
     }
diff --git a/tests/json/member-17.json b/tests/json/member-17.json
index 1dce126..078545f 100644
--- a/tests/json/member-17.json
+++ b/tests/json/member-17.json
@@ -24,7 +24,7 @@
         "mglTypeId": "MITGLIED",
         "beitragsart": "Voller Beitrag",
         "nachname": "Nach2",
-        "eintrittsdatum": "2003-11-17 00:00:00",
+        "eintrittsdatum": "",
         "rover": null,
         "region": "Nordrhein-Westfalen (Deutschland)",
         "status": "Aktiv",
diff --git a/tests/json/member_overview.json b/tests/json/member_overview.json
index c46ac9c..41c5e20 100644
--- a/tests/json/member_overview.json
+++ b/tests/json/member_overview.json
@@ -37,7 +37,7 @@
             "entries_geburtsDatum":"1991-06-20 00:00:00",
             "entries_staatangehoerigkeitText":"deutsch",
             "entries_nachname":"Nach1",
-            "entries_eintrittsdatum":"2005-05-01 00:00:00",
+            "entries_eintrittsdatum":"2005-05-01",
             "entries_austrittsDatum":"",
             "entries_genericField2":"",
             "entries_telefax":"+55111"