No errors at all, the form just reloads the page (but with # at the end of the address). The form is basically a load of checkboxes and buttons but looks like the:
<form id="filter_form" method="post" action="#">
<input type="hidden" name="country" value="1">
<input type="hidden" name="order" value="">
<input type="hidden" name="muscle" value="on">
<div class="filter_title" style="padding-top: 10px;"><a class="nav_title" id="type_open" style="display: none;"><img src="/images/site/arrow_filter.png" height="9" width="9"> Type</a></div>
<div class="filter_title"><a class="nav_title" id="type_close" style=""><img src="/images/site/arrow_open.png" height="9" width="9"> Type</a></div>
<div id="type" style="">
<div class="filter_filters"><label for="Bar"><input type="checkbox" name="type_2" class="filter_link">Bar</label>
</div>
<div class="filter_filters"><label for="Food"><input type="checkbox" name="type_3" class="filter_link" checked="">Food</label>
</div>
<div class="filter_filters"><label for="Powder"><input type="checkbox" name="type_1" class="filter_link">Powder</label>
</div>
<div class="filter_filters"><label for="Ready-to-Drink"><input type="checkbox" name="type_4" class="filter_link">Ready-to-Drink</label>
</div>
</div>
<div class="filter_title"><input name="Submit" type="submit" value="" id="filter_submit"></div>
</form>