Every liquid-cooled build falls into one of two camps, based around the tubing used. There are two types that the enthusiast community takes advantage of right now: hard tubing and soft. Each has its own advantages and disadvantages. Soft tubing, the most common type, is usually a form of flexible PVC, capable of being cut to length with relative ease. Available in many colors, it’s commonly found with an outer diameter of 13, 16, or 19mm, and can be used with a barb, or specially designed compression fittings, which are a combination of a barb, with an o-ring and compression cap on top.
Its successor—which is arguably more difficult to work with—is hard tubing, also known as hardline, an umbrella term for everything from acrylic, to copper, even glass tubes. Often requiring special tools to cut and shape, it’s a far more difficult material to manipulate, though it provides cleaner lines and tighter bend radii than its soft-tube counterparts. Acrylic was the first hard tubing used in liquid cooling, thanks to its ability to change shape when heated. It’s still available today, and is sometimes preferred to its PETG successor. To shape it, you simply place a silicon insert into the tube, heat evenly along the part you want to bend, and slowly bend it into the angle you require, before cooling it. Over time, it’s become quite an art form, with modders creating all sorts of complex and ludicrous angles, styles, and lines. PETG is a more complex polymer, designed to address acrylic’s lack of shatter tolerance, and is now one of the most common materials used by the hardline community. Hard tubing traditionally used what’s known as push fittings, but today most people use compression fittings, with two or three o-rings—two inside the push fitting, and one in the compression cap to reduce the chance of leakage.
For the rookie liquid-cooling enthusiast, it’s advisable to start out on soft tubing first, being the easier of the two methods, then try your hand at hard tubing at a later date.
Hardline cooling is popular and classy.
Soft tubing is far easier to install.