Hey, so I'm building a loop for my brother's PC. We're using an NZXT H200i, so to save space on the pump, we bought this combo https://www.aliexpress.com/item/10000411453657.html after Optimum Techs good review of it. However, the pump acts weirdly, for example, it just wont pump water most of the time. The motor is spinning, but it just doesn't push water. Then other times, it pumps but at a very slow flow. I say 10% of the time we could get it to spin normally. When it was in the system, tilting it to the front and power cycling a dozen times we got it to spin quickly as it should. When it spins quickly, the speed control and everything works. But after draining the loop, looking at the pump, and seeing nothing physically wrong, we can not get it to spin at the proper speed outside the case.
I recorded a video of it spinning slowly, hence having bad flow and being quiet, and while the system was tilted and it going "fast". Sorry for the bad phone quality. Is this pump defective and we should return it? Thanks for the help.
https://www.youtube.com/watch?v=gvFvfVuEYfc&ab_channel=Gecko.