nice, i had that kit for like a month. then went for custom watercooling

by the way, aluminium + copper not a nice combination. you'll get cloudy tubes in a week.

Actually this is a bit waste of time
Jump straight to a proper loop will be my choice
PM vlad or clawhammer for more info

Bro... for your tubing not being to be completely full, here's a tip that I use.
Very basic is to understand the physics of air/ water/ gravity, this is especially helpful when you wanted to drain your tubes in the future.

So, from the looks of it, if you can try to mount your reservoir higher, you will be able to fill up the tubes... what's happening now (I THINK) is because your radiator too very high up vs. your reservoir and inlet is coming from top. To see if my theory make sense, try tilting you casing sideways and see how the tube fills up itself...

As for your rad, you can mount it outside of your exhaust fan and check how much temp is affected... I expect not too much, and will make your overall loop much cleaner.

just my two cents