Step by step was written originally as a 100+ page course in koi health treatments for the advanced hobbyist for the AKCA koi health program and was adapted to be a book and broadened to encompass beginner to intermediate hobbyists as well as advanced health technicians.
If you know nothing at this point in time, or know lots this book will serve you well
Written in plain easy to read English even the science of koi health becomes clear, with typical doses given in both UK and US gallons every dose comes with icons of the national flag for each so no mistakes can be made.
Step by step is exactly that and does what it says on the cover. I.E. gives you many comic strip type pictures depicting the health issue being addressed so you can follow along at such a time that you may need to treat something topically.