Here is how I imagine you will set your Lamptron automatic fan curve, assuming you get the AP-45 fans.
You select the lowest automatic temperature, which is 25° C.
Than you turn down your fans to the fastest comfortable speed. The fastest that you want your fans to run when your computer is no under load. For me, it's 900 rpm, or 35% speed.
Than, you select the maximum speed you want your fans to run when under load. That should be 100%, or 2150 rpm for your build.
The upper temperature limit is automatically selected for you, 10° C above your selected lower temperature.
So any time your coolant is at or below 25° C, your fans will be silent. But as you put your computer under load, and water warms up, the fan speed ramps up, until they reach max speed at 35° C.
And btw, the Lamptron doesn't come with a water temp probe. You'll need to buy that seperately.