Looks like a massive problem
It turns out that when buying a liquid cooling system, you do not always get what the manufacturer claims. And the point is not at all in some advertising slogans about better performance, but in very specific parameters. An investigation by the author of the Igor's Lab portal showed that some liquid coolers simply do not use exactly the materials that the manufacturer claims.  ;
The main problem concerns copper in cooler radiators. As you know, copper has excellent thermal conductivity, but it is heavier and more expensive than aluminum, so it is not always used. The author examined six known liquid COs and found that half of them contained no copper. More precisely, there is no pure copper. And no, it was not replaced with aluminum, which would simply be an outright lie. Instead of copper, brass is used, which still contains copper.
But that's not all. Problems also related to chemical contamination, the presence of prohibited lead solder, the quality of mechanical processing, and so on. All this applies specifically to liquid CO radiators.
At the same time, the author says that those companies that sell these COs may not be to blame, because often they do not have their own production facilities, but rely on third-party companies, and here you simply need more thorough quality control on the part of the customer.
The author also adds that he purchased several more liquid COs from other manufacturers to expand his review.