Yes. If you use the latest version, it's actually the file "show_default" that you should edit and change the code:
<div id="hikashop_product_description_main" class="hikashop_product_description_main">
<?php
echo JHTML::_('content.prepare',preg_replace('#<hr *id="system-readmore" */>#i','',$this->element->product_description));
?>
</div>
by:
<?php
echo JHTML::_('content.prepare',preg_replace('#<hr *id="system-readmore" */>#i','',$this->element->product_description));
?>
<div id="hikashop_product_description_main" class="hikashop_product_description_main">
</div>