The Kumonryu is a Doitsu (German) koi that has a jet black pattern that emerges like billowing black clouds against a white background.
The black pattern is variable and unstable, disappearing with changes in the water temperature, reappearing sometimes as a completely different pattern.
For many of us, our ponds are beginning to warm (or will soon be). Water temperature, not the ambient air temperature, is the gauge for what to do and when to do it in regards to your pond. Water temperature should be checked at approximately 1 foot of depth. Avoid feeding your fish until the water temperature is consistently above 50 degrees Fahrenheit. This will also be the time to start adding spring maintenance bacteria and enzyme treatments.