How to tighten gates belt drive on Focus planet 8 the belt on my focus planet 8 is becoming a bit loose and I thought of tightening it. 

The rear wheel setup on the focus is similar to the one in the video from bikefriday below:

                
            

What is different is that my bike does not have the adjuster holes to change the tension. There is the big long thread, but at the end there is no hole for an allan key nor is there a hole for a screwdriver to adjust?

Pictures below:




Does anybody know how to deal with this?

Below are the pictures from the side:
sideview1


I imagined that the process should be: open the 2 bolts from the outside, then tighten the inside "bolt" on the chainstay. however I don't see a way how to perform the last step, as it is not a bolt nor a screw that i have on the inside chainstay.

thanks
It's hard to tell from your pictures, one from the side would be nice.  I did a search and came up with the following picture.



If this is what your bike looks like, then you need to loosen the two bolts I've labeled on both sides (4 total) and slide the wheel back until the belt is tensioned correctly. Make sure the wheel is straight and even on both sides when tightening everything back up. From looking at your pictures, it also looks like you should tighten the bolt on the inside of the chainstay where you've circled in red to prevent the wheel from slipping.