FaucetBox ready made script and it works a treat for bot traffic lol.

My idea was originally to use Fail2Ban and a custom filter to search logs on my server to limit POST requests within short time frames, it worked to a degree, within a few hours several hundred IPs were banned all similar IPs (thought that was a bit easy) Then incame more IP ranges each IP submitting less often. As it's a POST requests server doesn't log info maybe ModSecurity can be used to look in to the POST requests further 

Something is definitely up