Tanks! I watched one from the same people and it was only 2 minutes long and very general.
Google “Koi Everything” and many hundreds will be available on the sidebars, too. The one video about koi tank and the grower is similar to the one I raised over a 1,000 in. Used up a 60’ x 29’ valuable pole bldg. When I needed to restock, I moved the tanks to go water plant in the; rapid turnover, low mortality and high profit margins,
In 20 min, I could personally show you how to be a “pond manager”, eclipsing all the YT vids.