Hello Bit Tech! I am new to watercooling and have been flushing my rad(s) for a few days now. I started last Friday and spent time from 17:00 to 23:30 filling the rad (minus a break for some food), shaking it for 30s, emptying it. I probably flushed it at least a hundred times that evening, still gunk. To start I was using distilled only, but when it never ended I googled and people said tap water was fine as long as you flushed with distilled after. So I did that. Since I had gunk still after 6 or so hours I started googling and also asked on the /r/watercooling discord for advice. What I ended up doing last Saturday was hooking the rad up to my shower hose and flushing it with hot water for two hours. After that I pulled it out and spent the time between 15:00 and 21:00 manually flushing it again, this time with tap water until I got tired and flushed it 10 times with distilled. Today I pulled it out again to keep flushing and spent the past 3 hours manually flushing it. At one point I had 3 subsequent flushes with no particles, only for particles to reappear after that. All of the water, except for the time I had it hooked to the shower, has been boiling, or near boiling. The image I am attaching shows the last flush of distilled water I did for the day. There's still crap in there. What can I do to make it disappear? I am getting a bit tired of this to be honest and wondering if this rad is just ****. tl;dr: Flushed rad manually probably 300+ times as well as 2hour flush connected to shower hose. Still crap in the water. What do?