Site's under attack
 

My sites under attack by a massive amount of guests. They are from many different countries and they are browsing random pages on my forums and causing the database to strain. My host's already disabled it once and don't want them to do it again.

Site's url is www.simplexhacks.com

What should I do?

You mean, your site is under DDoS attack? Do you know who it might be, some competitor? Banned member? ... There isn't much to do except to ban those IP's via iptables, if you have root access to the server.

You sure it's a ddos attack? My site would be laggy and possibly off. It's alot of guests viewing random pages. not just one single page. The host said it was a php attack.

Do you have Google Analytics, or any other tracking option that would show you the referring visitor site?!

Are all IP's from the same country? Are they viewing similar pages, or it's all random like you said? ..

Theres currently only 239 online. That should not be an issue at all.
Your host will be able to tell you if there is a DoS attack.
Consider to install the bad behavior hack.

They cut it off for 5,000 guests earlier. I did signup for cloudflare though and am using it.

That's DDoS then. Just submit a support ticket if you see increased number of visitors, e.g. around 1,000.