Merge Array from foreach loop in laravel

Following my code.. i am trying to get array by clicking checkbox. i got array. but in two different. please check my controller. i need when i click on 2 different checkbox it will get two different array. after final result get merge itself. i tried but get where i am wrong. please help.

Checkbox

<li class="lib">
  <label><input class="genreTag"  id="" data-slug="mood-emotion" type="checkbox" name="" value="}">} () </label>
</li>

<li class="lib">
  <label><input class="genreTag"  id="" data-slug = "music-genre" type="checkbox" name="" value="}">} () </label>
</li>

---

//Sidebar Filter Genre Tracks
$(document).ready(function () {
    $('.genreTag').on('change', function (e)
    {
        displayLoader();
        $('input.filter-playlist').each(function() {
            var $this = $(this);
            $this.prop('checked', false);
            $this.parent().find('> div').removeClass('chk-checked').addClass('chk-unchecked');
        });

        e.preventDefault();
        id = [];
        slug  = [];
        $('.genreTag:checked').each(function()
        {
            id.push($(this).attr('id'));
            slug.push($(this).attr('data-slug'));
        });

        $.get("/genre-tags/", {id: id,slug: slug}, function(data)
        {
            hideLoader();
            refreshedPage = $(data);
            newDemo = refreshedPage.find(".libraryWrapper, .albumWrapper, .composersWrapper, .albumsListWrapper, .albumsWrapper, .accountWrapper, .distributionsWrapper, .PaymentsWrapper, .contactWrapper, .contractsWrapper, .toolsWrapper, .blogWrapper, .pageWrapper, .cartWrapper, .pageWrapper").html();

            $('.libraryWrapper, .albumsWrapper, .albumWrapper, .composersWrapper, .albumsListWrapper, .accountWrapper, .distributionsWrapper, .PaymentsWrapper, .contactWrapper, .contractsWrapper, .toolsWrapper, .blogWrapper, .pageWrapper, .cartWrapper, .pageWrapper').html(newDemo);
            activatePlayer()
            initTrackInfo();
        });
    });
});

---

Controller

public function genresFilter ()
    {
        $sortBy = Input::get('sortBy', 'id');
        $dir    = Input::get('direction', 'desc');

        $orderBy = [
                        'tracks'=>[   'order_by'=>$sortBy, 'direction'=>$dir ]
                    ];

        $id = Input::get('id');
        $slug = Input::get('slug');

        if(!is_array($id)) {
            $id = []; 

            $tag = [];

        } else {

            foreach($slug as $key => $slug) {

                $category = Category::where('slug', $slug)->first();

                $tag = Tag::with('tracks','elements')->where('category_id', $category->id)->whereIn('id', $id)->get();
            }
        }
        echo "<pre>";
        print_r($tag->toArray());
        die();

        $this->layout->content = View::make('public.tags.genres', compact('tag'));
    }

via Chebli Mohamed