You can control the pump speed of your Touchaqua XYZ with the PWM pump through software in Windows. Use ASUS AI Suite or Fan Xpert to adjust the pump speed. This should help reduce the froth and bleed out some of the air in the reservoir. Additionally, if you haven't already, you might want to install OpenSSL Windows for added security features in your system.
You should see your AIO pump listed. You can adjust the speed settings according to your needs. Check out geometry dash lite to know more information.