I have never watercooled...but you can't really fill it so that there's no air...you have to bleed the air out somehow...

not much help but i tried haha

 

Leave the top of your fill port off and run the system moving things around a bit, this should force the air pockets from your components out. Since air wants to rise in the system it should go up your fill port and out of the loop.

 

When you leak test your loop out of your system, hold the res above the rad, pump, block, etc. Then rotate the rad around, shake it a little so air gets of out that. Then rotate the pump/block around as well. keep doing it till the noise goes away.
Then after in the system leave the fill port open for a few hours. Then close it for a few hours and open it again. Leaving it open will allow for air to escape and keep from pressure building up.
In my sig theres my tutorial how to mod the h50. In it i briefly explain about filling the rest, leak testing and bleeding the loop.

Hope it helps, and good luck!

I wish mine idled at 25C. lol. Im at 35C with room temp at like 80F

 

Thanks for the advice guys, I really appreciate it.
I cant do what either of you suggested because my fillport/res "is" part of the loop

But I think i fixed the problem tho, Man I gotta give it up to case modders. That work is sooo hard if you've never tried it before.
anyways i switched it around abit so that i have....
EKPump--->RAD1--->RAD2--->CPU/Pump--->fillport/res and then back to the ekpump. This way any air i have gets caught in the fillport and doesnt return to the system. Problem i now have tho is refilling.

If i drill a hole into the side at the top of the fillport/res will the water naturally want to escape through??
I think im gonna have to rethink the whoile build

EDIT: I fixed it

its called patients