Corsair SP120 , Scythe GT120 , Cougar seem to be the go to rad fans for high pressure low noise.. You can read up on fans at
Matrins labs ..
I can tell you from experience that the GT120's do a very good job and are quite, I tried some LED fans just for some esthetics and they worked ok but when it started to heat up they really got load and didn't cool as good as the GT's at any range..
Do you know what kind of rad you will be using ? High FPI or low ? you need to know this for your fan selection.
Distilled water and kill coil is the best way to go IMO