For most anyone who has ever been to the farm, you know that “walking the ponds” is a daily activity from April to October.  For those of you who don’t know…we started breeding koi in the summer of 2002.  While we were successful at breeding, we ran into issues with keeping the fry alive.  We went through a few summers running into the same problem.  We were able to successfully keep some alive and they grew into beautiful koi; however, we need to be able to keep thousands of koi alive!  In talking with our mentor, Toshio Sakai (Isawa Nishkigoi Center, Matsunosuke bloodline), we shared with him the problems we were facing.  Little by little he shared his knowledge with us, but it was never black and white.  He offered small pieces of information in what seemed like riddles.  Adding to that the language barrier, it took us some time to figure out what his advice meant.  Over time, we learned that “walking” the ponds was one of the major elements in keeping the fry alive.

Pond being walked...notice the predator protection!

Our clay lined mud ponds have regular topsoil on top of the clay.  Gases naturally build up within the topsoil.  If you think of the topsoil layer like a sponge, pockets build up within the layer and if you step on the pocket, it releases the gas.  If the gases are not released they can be toxic to the koi.  Koi that are bigger typically root around the bottom looking for food, which helps to release the gases.  However, the fry are much too small and we need to do the work for them.  Once we learned this information our breeding program became much more successful.  That being said, when we started walking ponds in 2005 we walked each pond about 45 minutes to an hour, and each pond was walked once a week.  We thought that the longer we walked the better!  We still ran into a few problems the next few years with fry ponds “crashing.”  This year we took a very different approach…only walk the pond for 20 minutes and each pond is walked 2 to 3 times per week.  Knock on wood…no fry ponds crashed this year!!!  However, this summer season has been like no other summer in terms of weather.  We have experienced extremely cool weather for weeks at a time, as well as weeks of rain.  So if you were the koi breeder…what would you decide as the walking schedule for next summer?

One of the purposes of this blog is to share with you the daily maintenance jobs that we do at the farm.  These jobs change seasonally.  Normally most of the summer jobs are outside: stringing the ponds, walking the ponds, breeding, culling, etc.  We also test the water in the mud ponds on a daily basis.  Each day a block of ponds are tested so that each pond is tested at least once a week.  We primarily test the ph, Kh (alkalinity), oxygen, and temperature.  We have found over the years that oxygen depletion can happen rapidly and the results can be fatal.  To combat this, all of the ponds have aeration and are lightly stocked.  Also, during heat waves we will add more aeration to ponds that have lower levels of oxygen.

Reading the results from an oxygen test

Tip for Pond Owners:    Test your ponds on a routine basis!  We recommend testing ammonia, nitrite, alkalinity, ph, oxygen, and temperature (knowing your water temperature will help you determine when to feed a high protein food vs a wheat germ based food).  Set a consistent time that you test the ponds.  We always test our ponds between 9-10am.  Be aware that ph levels swing throughout the day, which is why we recommend testing at the same time each day.  If you have time to test twice a day, it’s always useful information to know your levels in the morning versus your levels at night for comparison.  Keep a record of you results.  Whenever we receive calls from people regarding issues with their pond/koi, the first questions we ask are related to water quality.