Question AIO Water Cooler not reaching desired rpms


Jun 19, 2018
Hello, i bought the Thermaltake Floe Riing RGB 360 TT Premium Edition a while ago. I was using a cheap AIO water cooler before buying this one. The thing is that i have tried everything, and i can't make the Thermaltake pump to run at its max RPM. It's supposed to run at 3600 rpm max, but i only can reach 1800, or less. and it's very frustating because this 200$ water cooler is cooling my cpu less than the 70$ cheap one i had before (ffs). If anyone can help me, it would be great.
I already tried changing it from "AOI pump" header from the motherboard to "CPU Fan" header but it doesn't change anything, idk what's wrong.
Ah, and yeah, the software is useless. i can control the fan's RPMs and they work fine, but on the AIO i only can change the RBG lightining.

The specs:

Cooler: Thermaltake Floe Riing RGB 360 TT Premium Edition

CPU: I7-8700k

Motherboard: Asus ROG STRIX Z370-H GAMING