Trying New Feed for My Koi

I normally feed my Koi with Hikari Staple (easy on my wallet) and supplement with Hikari Spirulina for the Koi with Red markings. Spirulina is an algae and research has been found to have a high content of the carotenoid colour pigment, which is very effective on the colour of Koi when added to their diet. That is, food mixing to balance cost and benefits. Hikari actually recommends a mix that includes a color enhancing diet comprising no less than 35% of the total quantity being fed.

I am now trying Saki-Hikari Growth Diet for my Koi since most of my new Koi are about 2 years old and still in their growing stage.

According to the label, this diet is able to “Promotes unbelievable growth and championship form!”. The protein content is at least 40%, compared to 35% for the Hikari Staple. According to the test results published on the packaging, this food is supposed to help grow a Koi 1.6 times better compared to the Hikari Staple diet. I am giving this a try although the relative cost of this food is about 2 times compared to the Staple food but if you want your Koi to grow big to its fullest potential, the first few years are the most important. Besides, this new feed also includes a probiotic, Hikari Germ which has many benefits, according to the manufacturer.

“This unique, beneficial bacteria overpowers bad bacteria within the intestine reducing it's propagation and ability to lethally infect your fish. Additionally, the proprietary Hikari Germ accelerates the digestive process thereby improving absorption and thereby reducing waste output.”

“Expect improved water quality and reduced filter maintenance when used as a daily diet.”

“Expect improved luster, reduced fatalities and fat-deposit-free growth as a result of the perfect ingredient balance.”

Let’s see in a few months’ time whether my Koi achieves what is claimed about the growth rate. I will not be too scientific about this, e.g. doing a controlled experiment and feed two batches or Koi with different feeds). Instead, I will just based on gut-feel since 1.6x vs 1x should be noticeable.

Right now, the only thing I noticed about this Koi food are:

* the Koi seems to feed with a greater frenzy with this new diet. Maybe they like a change of diet sometimes, like humans.

* the food pellets leaves a slight trace of oil on the water surface compared to the Hikari Staple.

I am doing a little survey on the actual Koi feeding frequency in this website. I would appreciate your participation; even if you don’t own a Koi or keep a pond.

BTW, I feed my Koi twice a day. Sometimes more.

Koi Size Seems Smaller in Pond

Have you notice that your Koi appears to be smaller when they are viewed in the pond compared to when they are in a bowl? Or is it just me? 

I remember occasions when I put my Koi into the bowl and they wow me with their size although they don’t appear to be that big when they are in the pond. I also remember occasions when I added a new Koi that I bought from the local dealer and they appear to be smaller once they are released into the pond!

Maybe there is a logical explanation for this.

Have you experience or heard about the Moon Illusion? The Moon Illusion is that the Moon appears bigger when seen near the horizon than when it is high up in the sky. Actually, the angular size of the Moon is unchanged as the Moon moves across the sky. It is just an optical illusion or the brain playing tricks.

It could be that the Koi illusion is due to the same effect. A Koi in the pond is like the Moon high up in the sky. There is little reference in terms of scale to allow your brain to calculate the true size. A Koi in the bowl allows your eyes and brain to compute the size more realistically. Hence the optical illusion.

Maybe that’s why the local Koi dealer always offer to catch the few Koi of interest to put into bowls for me to inspect closely. Is this part of good service or something else? Hmmm…

How to solve water quality problem in my Koi pond?

This is a question I often get from my friends after they have seen my pond or heard that I am a Koi keeper.

Many pond owners have built their first pond without understanding the need for a proper pond filter system. Often, these are DYI ponds or ponds build by housing contractors with little experience in Koi pond construction.  They fail to understand the need for a proper water filter system, specially designed for Koi fishes. A Koi pond without a proper filter system would often results in pond water quality problem.  Symptoms would be murky or green water that looks like pea-soup, unhealthy or dying fish, foul smell and all these despite regular back-breaking pond maintenance tasks.

Although water additives would often help fix the symptoms, the long term solution would be to invest in a proper Koi filtration system. Best is to plan, design and build it right the first time. For cases where the pond is already constructed, I guess the most practical way to solve your pond water quality problem is to install an external pond filter system. This avoid costly and time consuming reconstruction of the pond and reduce risk of losing your fish during the process of upgrading your pond.

A good filter system would have mechanical filtration, biological filtration, AND  allows for ease of regular filter maintenance (like backwashing of filters, partial water changes). If your budget permits, choose one with UV steriliser system that helps to kill parasites and algae cells in the water (cause of green water). Some even employ a vortex, centrifugal system to draw solid particles to the center of the filter for more efficient mechanical filtration. These external filter systems come in various models and design to suit the capacity of your pond and your budget. 

Even with a proper filter system, do perform your regular partial water changes to remove the nitrates.

Pond Aeration

Koi needs oxygen and so does the bacteria in the biological filter. Dissolved Oxygen level of 8 mg/litre in water temperature of about 25 deg C is almost ideal since it is almost at saturation point. I used a TetraPond water test kit to measure this. Plants (including algae) in the water also uses oxygen at night. Plants take in carbon dioxide and produce oxygen only in the day, during photosynthesis.

Besides the natural absorption that occurs at the pond water surface, any ways to agitate the water artificially will increase the oxygen absorption by the pond water. Pond designers often include a waterfall for aesthetic reason, as well as for pond aeration. Waterfalls also create the soothing sounds of gurgling water in my home. Waterfalls are ideal for informal pond design. Plants and rocks formation can create a beautiful natural setting. In the picture of my second pond (below), my waterfall is almost fully hidden by the plants (a large bird-nest fern, money plant(Epipremnum aureum), water pennywort and backed by heliconia rosetta).

In my third pond, I used a pot of over-flowing water that sits on a shelf. This then cascade down into the Koi pond through a small step down, bounded by pandan plants(Pandanus amaryllifolius). Other forms of water-feature designs are commonly used as well in Asia, most with feng-shui themes.

Some pond keepers uses an air pump with an air-stone (normally placed within the filter chamber to create streams of bubbles before the biological filter chamber). I don’t use this method in my ponds.

Instead, I use the venturi pipes (picture above). The venturi pipes are very cost effective in aeration. Water from the return pumps are forced through the venturi pipes at high speed and draws air down the air vent to create lots of bubbles at the outlet.

The 2 photos on the top show the construction of my venturi pie. One photo shows the view as seen from the outlet.

Placement and location of the venturi pipes is important. Where feasible, the pipes are arranged to circulate water slowly in a clockwise direction around the pond (circulation is supposed to be good for Koi) and moves dirt and debris in the pond towards the bottom drains using the centrifugal effect. The pipes should be placed about 4 to 6 inches below the water surface, not too deep as it will not work properly if placed too deep (unless you have a strong enough water pump!)

Recommended Book for Koi keepers – Koi Kichi

 

When I was starting on my Koi hobby and planning to build my first pond back in 1995, I did research on the internet and read/browse through many Koi books in the bookstores and library.

I came across this book by Peter Waddington, who is a Koi “Crazy” hobbyist with 20 years of experience, and lives in the UK. Although it was pricey, I decided to buy this book for keeps as the content within was exactly what a budding Koi hobbyist would need and this book was far better than the various cheaper Koi books at the local bookstores.

The book has 8 “sub-books” within, called Book One to Book Eight.

Book One provides background information of origin of Koi and their development.

Book Two provides good information on what are Koi’s environmental needs and what is involved in the Koi hobby.

Book Three is all about how to build a ‘proper’ Koi pond system. It describes various filtration systems, and also pond maintenance. The many photos of Koi ponds and drawings of filtration systems in the book are very interesting as it gives me ideas of what I should or should not include in the layout and design for my own Koi pond.

Book Four is all about the Koi appreciation and Koi hobby in general. Drawings to describe Koi varieties, patterns and classifications are included.  Photographs of show-grade Koi to illustrate traits of a good quality Koi are useful when you are ready to buy your first Koi.

Book Five describes Koi caring, feeding, diseases and medications.

Book Six describes how Koi breeders in Japan breed Koi and an amusing story of Peter’s attempts to breed Koi at home.

Book Seven and Eight provides some background of famous Koi breeders in Japan and how they conduct their business. Koi hobbyist would find this interesting later when they become serious in their hobby and are interested in keeping show-grade Koi, understanding their bloodlines and planning to visit Japan on a Koi shopping spree.

This excellent book was first published in 1995 and it was not available on the local bookstore then (and now as well!) so I bought mine through mail order. My copy came with a hardcover.

Koi Kichi (Paperback Edition) is available through Amazon.com now.