If you need to apply different sizes to an image added with ACF the I’ve found the best choice is to have it return the attachment id rather than any of the other things it can return. Then it is simple to us a different images sizes of the same image.
$attachment_id = get_field('taximage', 'industrygroups_'.$lc->term_id);
if ($attachment_id) {
$image = wp_get_attachment_image_src($attachment_id, 'my-custom-size');
if ($image) {
?><img class="img-responsive img-thumbnail" src="<?php echo $image[0]; ?>" /><?php
} // end if image
} // end if attachment_id
