You would have to edit the file show of the view product and change the code displaying the image so that it displays your images using art zoom.
Here is something which should do the trick (not tested) if you replace the code generating the images by it in the div <div id="hikashop_main_image_div"> there:
$config =& hikashop::config();
$uploadFolder = ltrim(JPath::clean(html_entity_decode($config->get('uploadfolder'))),DS);
$uploadFolder = rtrim($uploadFolder,DS).DS;
$uploadFolder_url = str_replace(DS,'/',$uploadFolder);
$thumbs = array();
$images = array();
foreach($this->element->images as $image){
$thumbs[] = $uploadFolder_url.'thumbnails/'.$image->file_path;
$images[] = $uploadFolder_url.$image->file_path;
}
echo JHTML::_('content.prepare','{artzoomin tinyImage="'.implode(',',$thumbs).'" smallImage="'.implode(',',$thumbs).'" bigImage="'.implode(',',$images).'"/}');