If you’re planning on water cooling, you have quite a few choices to make. Aside from tubing size, mounting options and a plethora of manufacturers to choose from, you also have to decide what type of a loop you want your water to run in. You have to decide if you want to run an inline or submerged configuration. The leading factor in this is what type of pump you buy and also what (if any) fill/bleed solution you buy. Now when the system is running and everything is fine, you probably could care less how your fill/bleed solution works. When it comes time to slap on your shiny new chrome water block and you have to drain the system is when you finally learn you should have gotten a reservoir.

Using a regular fill/bleed solution is just a hassle. To drain the system you have to pull out tubing, and fiddle with tubing orientation to get all the water out. Filling is an ever bigger hassle, having to put as much water as you can at a time with a funnel. With a reservoir, to drain the system, you simply have to unscrew the reservoir cap, and turn the reservoir over. To put things simply, you should get a reservoir.