Rials, array of checkbox values not submitting (acts as taggable gem)

I have a painfully simple form that is meant to submit and array of "interests" to my user (I am using acts_as_taggable gem). This just isn't submitting the values despite the HTML output looking right (to me at least). Been looking at this for a while.

        <%= simple_form_for @user, html: { multipart: true }, remote:true  do |f| %>
            <% @interests.each do |interest| %>
                <div class = "InterestIconContainer">
                    <%= image_tag 'InterestIcon.png', :class => "InterestIcons" %>
                    <%= f.check_box :tag_list, {}, interest, "nil" %>
                    <div class = "InterestLabel"><%= interest %></div>
                </div>
            <% end %>
            <%= f.button :submit, "Update", class: "btn btn-default btn-sm", id: "SecondUpdate", data: { "loading-text" => "Updating..." } %>
        <% end %>