diff --git a/app/Models/Coverage.php b/app/Models/Coverage.php
index aaf95b2..4dbc391 100644
--- a/app/Models/Coverage.php
+++ b/app/Models/Coverage.php
@@ -3,6 +3,7 @@ namespace App\Models;
 
 use App\Models\Dataset;
 use Illuminate\Database\Eloquent\Model;
+use DateTimeInterface;
 
 class Coverage extends Model
 {
@@ -47,6 +48,16 @@ class Coverage extends Model
     {
         $this->attributes['time_max'] = empty($date) ? null : \Illuminate\Support\Carbon::createFromFormat('Y-m-d H:i:s', $date);
     }
+        /**
+     * Prepare a date for array / JSON serialization.
+     *
+     * @param  \DateTimeInterface  $date
+     * @return string
+     */
+    protected function serializeDate(DateTimeInterface $date)
+    {
+        return $date->format('Y-m-d H:i:s');
+    }
 
     /**
      * relationship to dataset
diff --git a/app/Observers/DatasetObserver.php b/app/Observers/DatasetObserver.php
index 247534f..45fee6b 100644
--- a/app/Observers/DatasetObserver.php
+++ b/app/Observers/DatasetObserver.php
@@ -6,6 +6,7 @@ namespace App\Observers;
 use App\Models\Dataset;
 use Illuminate\Support\Facades\Log;
 use App\Library\Search\SolariumAdapter;
+use \Exception;
 
 class DatasetObserver
 {
@@ -92,10 +93,8 @@ class DatasetObserver
             // Opus_Search_Service::selectIndexingService('onDocumentChange')
             $service = new SolariumAdapter("solr", config('solarium'));
             $service->addDatasetsToIndex($dataset);
-        } catch (Opus_Search_Exception $e) {
-            Log::debug(__METHOD__ . ': ' . 'Indexing document ' . $datasetId . ' failed: ' . $e->getMessage());
-        } catch (InvalidArgumentException $e) {
-            Log::warning(__METHOD__ . ': ' . $e->getMessage());
+        } catch (Exception $e) {
+            Log::error(__METHOD__ . ': ' . 'Indexing document ' . $dataset->id . ' failed: ' . $e->getMessage());
         }
     }
 }
diff --git a/composer.lock b/composer.lock
index ea15f55..517cfb9 100755
--- a/composer.lock
+++ b/composer.lock
@@ -2200,16 +2200,16 @@
         },
         {
             "name": "nesbot/carbon",
-            "version": "2.48.0",
+            "version": "2.48.1",
             "source": {
                 "type": "git",
                 "url": "https://github.com/briannesbitt/Carbon.git",
-                "reference": "d3c447f21072766cddec3522f9468a5849a76147"
+                "reference": "8d1f50f1436fb4b05e7127360483dd9c6e73da16"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/briannesbitt/Carbon/zipball/d3c447f21072766cddec3522f9468a5849a76147",
-                "reference": "d3c447f21072766cddec3522f9468a5849a76147",
+                "url": "https://api.github.com/repos/briannesbitt/Carbon/zipball/8d1f50f1436fb4b05e7127360483dd9c6e73da16",
+                "reference": "8d1f50f1436fb4b05e7127360483dd9c6e73da16",
                 "shasum": ""
             },
             "require": {
@@ -2289,7 +2289,7 @@
                     "type": "tidelift"
                 }
             ],
-            "time": "2021-05-07T10:08:30+00:00"
+            "time": "2021-05-26T22:08:38+00:00"
         },
         {
             "name": "nikic/php-parser",
diff --git a/config/solarium.php b/config/solarium.php
index bea3fb2..d13c652 100644
--- a/config/solarium.php
+++ b/config/solarium.php
@@ -5,7 +5,7 @@ return [
         'repository' => [
             'host' => env('SOLR_HOST', 'repository.geologie.ac.at'),
             'port' => env('SOLR_PORT', '8983'),
-            'path' => env('SOLR_PATH', '/solr/'),
+            'path' => env('SOLR_PATH', '/'),
             'core' => env('SOLR_CORE', 'rdr_data')
         ]
         ],