How can I make your forms more secure against spam?

I am running some old websites which we are in the process of updating but it is a massive project and many of these sites will not even be addressed until next year. That being said, we are getting a TON of spam every day. I need to know if there is something I can do to change this. You've helped me out in the past and the last thing i was told to do was run your form in an iFrame. I've done that, but we are having a TON of spam issues again and I workable solution.

The site in question which is giving me the most grief is http://www.lgtile.com/esd-vinyl-tile-order.php

Please let me know what I can do.

Thank you!

Hi, you can use the "Unique Submission" feature under "Form Limits" of your form "Preferences".

Select "Loose check" to prevent users from submitting the form multiple times from the same computer. You can select "Strict check" to prevent multiple submission from the same IP address. This will help you to prevent spam, let us know if you have more questions, we will be glad to assist you.