for your controller:
use Phalcon\Validation\Validator\Email;
$validation = new Validation();
$validation->add('user_email', new PresenceOf(array(
'message' => _('Email es requerido')
)))->add('user_email', new Email(array(
'message' => _('El formato del email no es valido')
)));
$messages = $validation->validate($a_post);
$s_error_validation = '';
if (count($messages)) {
foreach ($messages as $message) {
$s_error_validation .=$message . '<br>';
}
throw new \Exception(_($s_error_validation), self::BTS_CODE_SUCCESS);
}