As a pond owner and koi hobbyist you have some growth and color decisions to consider. The general knowledge towards these decisions comes from time and experience as a hobbyist and more importantly some self-education and/or exposure to the principles in play on the subject of growth/color. What do you want your koi to do within the confines of your pond system? I’m going to have to stay with generalities as I introduce you to some points for consideration and while all this stuff has been seen in print or video not all agree with some of the finer points – that’s my disclaimer LOL but I believe in what I’m about to pass along in this article.
In the beginning most backyard koi hobbyists want pretty and healthy koi that get bigger with time and are friendly and that can be your continuing goal even after reading this article.
Then all sorts of things start to happen over time and for this subject they may include things like: my koi don’t look as nice as they use to; the loss of color; gotten a lot darker; the white is changing (usually not as nice); have a lot of new little spots (mostly black); not grown much; gotten too big for my pond; are skinny or even fat – so what am I doing wrong?
Well we need to become a little more familiar in three areas - while asking yourself what do you want your koi to do? They are the individual koi purchase, your pond and water quality and finally nutrition and feeding schedule.
The koi is a very important part of the puzzle. The more you know the more you can expect certain results. Pick a number say $10/$100/$1000 but on your low end you may not need a host of info to get what you want/expect from the koi. However, with more expensive koi, especially if thinking a show koi - well you need to know a lot more in my opinion – breeder, bloodline, past results of offspring that are now older, etc. This is considered the genetic profile. Folks, there are books covering just this subject and make for some interesting reading. So we now have for your consideration - What are the wants/ expectations in visible terms for a successful Return on Investment. (ROI)? Yes, how long do you want/expect to keep your koi, how big do you want/expect it to get, when do you want or expect it to look its best/what do you want to do with the koi once your ROI has been accomplished???? So you say you have never considered these things – well now may be the time to give it some consideration and what are the things you can do to assist your now established ROI as we move on to the next two important areas.
Water quality is a major area and is not without its direct effects on both growth and color in meeting your expectations established at time of koi purchase. In general soft water is advantageous to the development of red color and lengthens the time for complete color development, while hard water is said to advance black color and be to some degree responsible for small black spots (shimi) on your koi and generally reduce the time for finished color development. Koi suffering from stress from a host of water quality issues to include long term low level issues are said to suffer both in growth and color. Studies of higher levels of Total Dissolved Solids (TDS) resulting in increased water hardness have demonstrated to reduce growth potential as has oxygen below saturation levels. Japanese koi breeders have expressed that higher oxygen levels increases koi activity leading to increased food requirements and associated increased growth. Higher Oxidation Reduction Potential (ORP) readings are thought to be too oxidative and present a (possible) negative effect on koi color pigment cells. I often refer to ORP as your pond’s pollution index. Finally, studies from the UK have reported higher koi grow rates in soft water conditions. So water conditions should be taken into consideration and maybe modify some of your answers or even koi purchases to the questions presented earlier. Bringing all 3 colors of a show quality Showa to up and finished at the same time should not be left to chance.
So that leaves us with nutrition and associated feeding schedules, for which there are again books on just this subject, but in general how you have answered the earlier questions should assist you with your feeding plan. Nutrition is obviously directly related to both growth and color but it has been said that when a koi is getting pounded with growth feed components it cannot keep up with color at the same time and that color has to catch up later and sometimes falls short of goal. Your koi goals are of significant importance especially your answer to when you want your koi during their life span to be their best and what you initially purchased. Males are said to finish sooner than females and if your koi purchases are already farther along with color development (very common) then they are going to finish sooner and they may need to be moved along to our club annual auction after just 4 to 6 years. It’s been said many a time that no baby champion has ever been a later grand champion. But you decide when your ROI has been accomplished and time to move a koi along. A lot of backyard koi ponds are not large ponds and while koi will still under the right conditions grow large in small ponds it may be desirable to keep growth below the koi’s potential and nutrition is a way to do this to some degree. Yes, you need to establish in spring a good estimate of pond total koi mass (weight) and for okay survival feed 1% of total weight; for limited growth and maintain color feed 2% of total weight and for maximum growth and color 3% of total weight as a daily feed requirement. I don’t want to complicate this but the aforementioned feeding schedule is for adult koi (say 4/5 years old) and for young koi you double the percentages. When the daily feed amount is divided into several feedings per day growth rates are said to improve. Unfortunately, when you have koi of all sizes in your pond the little ones may not get their fair share of the feed as the big koi quickly scoop up surface food. I think I’ve observed less of a problem with this when I do my twice a day sinking food feedings. Growth note: when your 9 to 11 inch one year old koi grows to 16 or18 inches in one summer you have not had an outstanding growth year, but only average at best as koi’s largest growth rates are realized in the first 3 to 4 years of life.
So with a koi ROI plan coupled with an ongoing increased attention to koi knowledge, water quality and nutrition your level of hobby satisfaction will be increased and hopefully keep you involved in the hobby, while sharing your gained knowledge with fellow club members.
While growth and color are an impossible subject to cover in this basic introductory article, I hope I’ve tweaked your interest to further explore the subjects and give some consideration to the info as it affects your next beautiful koi purchase and that it exceeds your established ROI.