Many veteran Koi fish lovers reluctantly quit the hobby, all for one reason:
Hikui (skin cancer among Koi fish)
In order to prevent this incurable, ugly-looking skin disease, the uncompromised way is to keep the filter clean at all times.
The common method used is regular and thorough manual works.
Crosslink prefer the simple straight forward and yet conservative method of spending
at least 1½ hour daily to thoroughly clean the filter
and in the meantime, aerating the bacteria (no doubt aerobic bacteria is much healthier than anaerobic).
Nevertheless, as good as the idea sounds, the amount of effort required is too exhausting for most hobbyist to handle unless it is an automatic system; a system which I am offering to you.