How should I set up a drain in my system?

There are three main ways to set up a convenient drain, which you’ll generally want at or as near the bottom of your loops as possible. If your reservoir has multiple inlet ports and a spare one at the bottom, oftentimes you can set up a drain there by threading a drain valve directly into it. If not, an in-line drain can be made by threading a T-adapter (sometimes called a 3-way adapter) into a component, having your tube run out one of the remaining ports and the drain coming out of the other. The most common place for this is a reservoir’s outlet port. Another in-line option is in the middle of your tubing, which will again involve a T-adapter, but will have two tubing fittings rather than threading into a component.