When Reddit user CrackerCortex's dog passed away, he was devastated to say the least. So to take his mind off of the pain he looked to the outdoors, specifically his backyard, to find a new outlet for his time. He decided to build a concrete koi pond in his backyard almost entirely by himself. But what started out as a pleasant koi pond ended up becoming an entire outdoor pool surrounded by rocks, complete with a grotto, a kiddie pool for his son, creeks, and much more as you'll see.

Check out this amazing DIY below.