same as me NAC
my water also sowly gets hotter. but chech this out:
as i said, i have a radiator, its inside a drawer, next to the case (my case cover is also off, just have a towel on top of it to cover the water lines ( i have cats you know).
when i keep the drawer closed, the water gets hotter during the day. (cpu temp hits ~35 when idle)
one day i said...hmm, let me open the drawer as long as i am next to the computer, playing or writing labs...using it.
and guess what, the water temp cooled down in about 10 min. i can feel it with my finger. it cools down in 10 mins. thats how good and useful the radiator is. it cools the water in 10 mins, dramatically, so i can feel it with my finger, and it has no fan on it, just the air it comes in contatct with when i open the drawer.
ican imagine much better results when i put a fan on it
if i could only find a way to keep my cats away from the water lines, or drinking the wetted water from the reservoir, i would keep the drawer door open at all times.
bythe way, under heavy usage, (3D games and some other applications on) my temp never went above 45 celsius.
before, with a fan, i would go to 60 celsius
now this is a good improvement
i am so curious how good it will be when i figure how to put a fan on the radiator, considering its out of the case.