H150i Pro - Custom Fan Curve

So I am use to air cooled where I could set the fan curve based on CPU temp. Not complaining, but need alittle guidance on setting a custom fan curve for the H150i Pro based on coolant temperature. \

Is there a general coolant degrees -to- fan RPM rule ?

Generally for air cool I do the 40c=50%, 50c=60%, 60c=70% and so on.

No, there is no specific rule and since coolant temp changes are small, changes to room/case temperature have a heavy influence on your settings. My general recommendation is to power on and let the PC sit for 10-15 minutes. This is your baseline level. Set the fans to a low and comfortable speed for desktop work. Then do the heaviest thing you normally do, whether it’s gaming/renders/encoding or whatever. Note the coolant temp and set the fans to highest speed you are willing to tolerate. Then back it down 100 rpm. This is the working part of the curve and all you really need to do.

From a practical sense, leave yourself 2-3C after the idle temp before you begin your slope up. You don’t want small daily fluctuations in room temp to drastically alter your fan speed. You can save the 100% fan blast for an out of reach point like 50C. You should only get there if something has gone wrong. Aside from that, it really doesn’t matter. Set your fans for noise tolerance. You can’t overheat with a working cooler and certainly not a 360mm. Fan speed can only alter coolant temp and the bulk of your cpu temperature is voltage based. You don’t need the fans to be reactive. As long as they are spinning, the cooler is removing waste heat. Slow and steady will get the job done.