Can I connect one D2 to a powered USB hub ??

Okay my setup consists of two kontrol D2's one Midi Fighter 3D one Kontrol F1 a Machine Mk2 which are all connected to the back of the D2's. and my 900 nexus is on its own port of course. I do have an external HD with all my music is it possible to connect one D2' daisy chain to a Dlink 7 port powered hub and then connect my external HD on the same powered hub so essentially I have two powered hubs connected to my Macbook pro ?. as a note I did try it and it seemed okay just want to make sure here if that's fine.

 

I actually just connected the DJM 900 to the back of one of the D2's as it said in the manual it was okay to connect an audio interface and used my other port on my macbook pro for the Hub seems to be working great it seems in the manual it says the d2's need to be on there own port not connected to another hub.