I was wondering is there any way to setup a HOB filter to hold some cheato. I have the HOB running with no media just helping circulation. Ive read some post where people have it in their sump and it does miracles for nitrates. Only problem is, I dont have a sump. My nitrates aren't exactly high, but i figured the filter could be used for something good. Its an emperor 400 so i have a good amount of room in the back to work with. Any suggestions or links would be appreciated. BTW where do find cheato?