when I first start out, more than half of my stock ended up dead within first 6 to 8 months but I didn't give up the hobby. it was a tough learning process on my own. I made a lot of beginners mistakes. I did read a lot of stuffs on how to care for koi but real life application is a bit different especially how to caring for sick koi and getting the water condition right and maintain it. I am still learning on how to keep my koi alive but now I got some help from friends and KB.
my fish are healthy and growing fine now.
Steve