I was unable to find a solution for the following scenario: 
I have a three different categories for website access : 
unlimited, one that can access entire web except fb, youtube, twitter. and third that can access only few sites. I can identify the user by the ip address. 
No problem so far, but all users must have a 30 min daily quota to access any website on the web. I'm unable to find a solution for this... Is it even possible on DFL-800? 
Thanks in advance.