In your AIO manual, page 12, it's shown that you need to connect the rad fans using a Y-splitter to your MoBo. Since rad fans are 4-pin PWM fans, which fan header you connected them?
As far as controlling fan speeds, that can be done via BIOS. E.g if you have your rad fans connected to the CPU_FAN2 header, you need to set custom or automatic fan profile for CPU_FAN2 header within BIOS.