My fish die time to time I recently had a 7 inch cichlid and a 12 inch pleco. They died from columnaris.
The quote of a poor fish keeper. You shouldnt lose fish from time to time. If your fish die then its your fault or a accident. When my fish get ich i turn the temp up, add some salt, and add a pump or 2 to it. Ive only had problems with ich 3 times in 10 years. I have had maybe a handful of fish die on me that i would say are my fault and it made me a better fish keeper. Sucks when you lose fish but it should teach you what to do next.