Run the cords into an area not directly visible, such as behind the tank, the next step is imperative, never look in that area again!!!
It is frightening how many cords and wires we accumulate! In all seriousness though, here's what I did.
With my apex EB8 and other hardware that has wires running to and from it, I mounted them on my cabinet door. I paint a peice of wood white just smaller than the doorframe on my cabinet, then used some wood blocks to mount the wooden panel on the back of the door but raised up from it, so there's about and inch or so gap between the front panel and the door. Prior to all this I measured out where the hardware would fit on the front panel, and cut 1" slits that would be under and above each peice of hardware.
Once the hardware is mounted, run the cables into the slits and behind the front panel, this makes it look a lot cleaner. But then there is still a big bunch of cords that you have to deal with.
For me, I took any excess length for each cord and looped it around my hand, cable tied it to keep it in a loop, and placed behind the tank tank cabinet, whilst trying not to mix them all up, as one day you will need to access one of those cords individually.
Hope this helps