First, you also need two pumps for cold and hot loop. Second, Pelts are square 40mm to 62mm square and need a block fully cover them. Most waterblocks today are small and round. This means you have to buy x2 Kraken kits. Better off building a kit, it's cheaper. Then you can run off computer PSU but pelt can draw 10a to 20a from 12V line. A dedicated 12V or 13.5v psu is recommended. As mentioned, the cold side builds condensation, especially at idle when there is less heat. It's easier to condensation proof a direct die pelt and single stage VS cold and hot loop. I've done all three and even dunked radiator into dry ice alcohol bath. Setup can survive a few drips and turned off ASAP. but never sitting water.

Finally, the heat from pelt can be equivalent to entire PC rig, +200W of heat dissappated. A small room can get hot real fast.