Cloning your site is just another level in fix wordpress malware scanner which may be very useful. Cloning simply means that you have backed up your website to a totally different place, (offline, as in a folder, in order not to have SEO problems) where you can access it at a moment's notice if the need arises.
This is great news as it means that there's a strong community of users and developers that can enhance the platform. However there's a significant group there will always be people who will attempt browse around this site to take down them.
For me it's a WordPress plugin. They are drop dead easy to set up, have all the features you need for a job like this, and are relatively cheap, especially when compared to having to employ someone to have this done for you.
Along with adding a secret key to your wp-config.php file, also consider altering your user password into something that's strong and unique. A good idea is to avoid phrases, use upper and lowercase letters, and include numbers, although wordPress will let you know the strength of your password. It's also a good idea to change your password frequently - say once every six months.
Always keep in mind the security of your sites depend on how you manage them. Make certain that you follow these tips to prevent hacks and exploits on websites and your own blogs.