Yessir. To be honest it'd be much easier to go with a pre-built loop but I wanted certain aesthetics. A custom loop also gives me more flexibility for upgrades since it's not a closed system.
The process of loading the coolant was pretty easy, as you can just use distilled water with some kind of anti-algae additive or premix. The hardest part for me was bending the rigid tubing just right so that I would fit perfectly and I wouldn't get any leaks. If i had to do it again I'd probably go with soft tubing, as it's a really quick and easy setup.