NEED ADVICE: AIO water level?

[j.falk]

I finally have my new AIO nano tank set up. This is the first one I've ever had so I'm not sure how high the water needs to be in the back chamber? I'm assuming so that everything is covered and working smoothly. Also, how do you tell when it needs topped off since the water line in the front part of the tank will always be consistent?

 

[j.falk]

Never mind, I figured it out by watching an Innovative Marine video.