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  • 03/08/2018 7:04 AM | Anonymous member (Administrator)

    Water from a household tap, a borehole or well, or rainfall will have unique properties and individual chemistry influenced by the location.

    No two ponds are identical in respect of their water chemistry or biology and many factors will naturally differ. It is not surprising that, the solution to a water chemistry issue that arises in one pond could make matters worse in another. A genuine knowledge of water science requires study at a molecular level, and an understanding of the role of water in Koi physiology and welfare is also needed to be able to offer advice .However, this is not essential for those hobbyists whose goal is simply to provide perfect pond conditions that will support their Koi for life.


    Measuring the pH of pond water tells us the hydrogen ion concentration, a value below 7 is acidic and above 7 is alkaline. Koi are capable of making adjustments internally in order to live in pond water with a pH between 7 and 9 although values over 8.5 may need monitoring to ensure they are stable. The optimum pH for Koi health, growth, and longevity is 7.5 - 8.0. This value is based on research carried out in UK water in my facilities with thousands of Koi for over 30 years. However, ideal conditions may well vary depending on the objective. For example , a Koi keeper may find his water chemistry supports the well-being of his Koi, although it does not preserve the highly prized red colour cells in some of his Koi varieties. Whilst genetics is the major influence, water chemistry has a minor role in colour retention. The pH in a Koi pond must be stable and this means all the changes that occur should be natural and therefore gradual. Water temperature, daylight length, the seasons, as well as the weather can all trigger chemical reactions and Koi have to adapt or they become unwell. Most hobbyists will have seen a Koi in the early morning suddenly dart across the pond surface on one side while adjusting to the new conditions. Some Koi are more sensitive and not all will react in the same way. If a pond with a normally stable pH suddenly alters it will upset the Koi and they may become listless and stop feeding. A more serious impact on their well-being is likely if the pH is in a state of continual fluctuation. If the pH alters, by more than 0.2 most Koi will release stress hormones as they attempt to adjust to the changes and having to adapt for long periods puts their survival at risk if the pH is not quickly stabilised.


    Although KH and pH have to be tested separately to assess how the pH is supported, they are closely associated, as it is by testing KH that the buffering capacity of the pH is revealed. It simplifies water chemistry to state that the pH will always remain stable if the KH level is in excess of 85 - 90 mg/L. At that level, fluctuations are far less likely but we have to keep in mind that pond water is less stable than tap water due to the numerous influences on it, particularly the pond filter system. In ponds, the pH can crash whereas that is not an issue in tap water as it is prepared and monitored by the water suppliers. There are many anomalies in respect of KH as the levels vary around the UK. In some areas, a KH of 1.0 does not always trigger an immediate pH crash. The Koi could remain safe until a pond event takes place such as the introduction of a treatment product. It is possible that as the product goes into solution it will interfere with the delicate knife-edge chemistry that has kept the koi alive until the inevitable crash. Some of the ways in which koi can be protected from a pH fluctuation or crash are listed below. K H buffering with bicarbonate of soda: The KH level of a pond can be raised by adding sodium bicarbonate at 100 gms in 1,000 gallons daily until the level is stable. The drawback with this method is that if there is an unknown reason as to why the pH decreased or crashed , sodium bicarbonate may not hold the level and it will drop yet again. This then adds to the fluctuations the Koi experience and avoiding fluctuations protects the Koi. If daily doses are needed, the Koi keeper can never forget to buffer let alone take a holiday and in such cases, this cannot be seen as an ideal solution. Many buffering products on sale in aquatic outlets are also based on sodium bicarbonate.

    Source: Paula Reynolds, Bsc, PhD,BA - Paula an aquatic patho-biologist, runs Lincolnshire Fish Health Laboratories and Research Centre a company that specialises in research into fish diseases for vets, fish farmers, hobbyists and the aquatic trade in England.

  • 02/16/2018 6:45 AM | Anonymous member (Administrator)

    There is a new monitoring system available for Koi ponds that measures pH and KH3 (not TAN), as well as temperature and water level.  It graphs the results of pH and KH3, and sends alerts to your phone or computer.  WOW!  More info and the web site link below the break...


    Visit their web site for full information about the device!

  • 02/03/2018 7:52 PM | Anonymous member (Administrator)

    More than three-quarters of the earth's atmosphere consists of nitrogen, yet only four-hundredths of one percent of the mass of the oceans, atmosphere, and earth's crust is composed of nitrogen.

    Although nitrogen is not a major component of oceans and land masses, it is an essential element for the formation of proteins in both plants and animals. Rainwater does the critical job of transferring nitrogen from the sky to the soil.

    The Chemistry of Nitrogen

    Nitrogen gas is a very stable two-atom molecule that doesn't easily interact with other atoms or molecules. For example, although three-quarters of every breath you take consists of nitrogen, none of that is metabolized by your body. The same is true of nearly all plants -- they can't take nitrogen directly from the atmosphere. In fact, legumes that can take nitrogen from the atmosphere don't do it directly, but through a symbiotic relationship with "nitrogen-fixing" bacteria in their roots. The bacteria "breathe" in nitrogen and convert it to compounds that the roots can absorb.

    Nitrogen and Water

    Nitrogen's chemical stability means puree nitrogen doesn't mix very well with water. But nitrogen compounds, such as ammonium and nitrates, do mix with water. If those nitrogen compounds exist in the air, they can mix with water and come down with rainwater. The question then is, how can stable nitrogen molecules convert to nitrogen compounds? The answer is that it takes energy. For example, lightning provides enough energy to split nitrogen molecules and stimulate the formation of nitrates -- molecules with nitrogen and oxygen molecules. Bacteria decomposing animal manure and internal combustion engines are also sources of energy that produce nitrogen compounds that can end up in the atmosphere.

    Nitrogen in Rainwater

    A 2004 study of the chemical composition of rainwater at 48 sites in 31 states found nitrates in nearly all the samples, although there was a high degree of variation in both time and space. Several studies in the 1990s showed that locations along the coast of the Gulf of Mexico could expect to get 18 pounds of ammonium and nitrates per acre per year from rainwater. That's about a tenth of typical nitrogen requirements for growing crops.

    The Good and the Bad

    Because rainwater contains nitrogen in forms that plants can absorb, and plants need nitrogen to grow, farmers have noticed that rainwater stimulates more plant growth than water from other sources. That's good, in that farmers don't need to apply as much artificial fertilizer. However, in some cases human activities result in an excess of nitrogen in rainwater. That has the effect of throwing off the balance in some fragile ecosystems where some plants -- typically algae -- that are normally limited by a lack of nitrogen now have enough extra nitrogen from rainwater to choke out other organisms.


        University of Wisconsin: The Elements
        Carleton College: Rainwater Chemistry Across the United States
        Highlights of Agricultural Research: Free Nitrogen from the Sky?
        Wisconsin Technical College System: Plants Prefer Rainwater
        National Atmospheric Deposition Program: Nitrogen in the Nation's Rain

  • 01/22/2018 9:05 AM | Anonymous member (Administrator)

    Koi whiskers are known as maxillary barbels.

    They are slender, whisker-like organs covered with taste buds and olfactory sensors (nose) to help them smell food. This is especially true as Koi ancestors, common carp, were scavengers and foraged in murky water and muddy pond bottoms. This sense allows them to taste food before ingesting it. Koi have one set of barbels on each side of the mouth, located on the upper lip, for a total of four barbels. Barbels are a distinct feature to distinguish Koi from goldfish, which do not have barbels. Barbels can be seen on young fry if you look closely. There are a few other species that also have barbels, including Goatfish, Hagfish, Sturgeon and Zebrafish. 

  • 12/20/2017 6:57 AM | Anonymous member (Administrator)

    We are constantly reminded not to feed our Koi too much - both for the sake of Water Quality, and for the health of the Koi.  And this time of year, some of us are not feeding at all because the water temperature is blow 50 degrees.  But is it possible to feed the Koi too little?

    First, we know that Koi food should be high protein year-round.  It was previously thought that Koi benefit from feeding a lower protein level in the cooler waters of spring and fall, but now it is agreed that we should feed a single, high-protein feed year-round, and vary the quantity based on water temperature.  Another thing we know is that Koi growth rates increased by 60% when they were fed 3 times a day verses once a day.  Remember that Koi are grazers, and benefit from more frequent and smaller meals.  So take the quantity you are planning to feed for the day, and split it up between the feedings.

    For other fish, it is recommended to feed them 0.5-2.0% of their body weight.  For Koi, it is suggested to feed between 1-3% of their body weight. 

    But does that work?  The weights of Koi vary drastically even if they are the same length, and most of us do not weigh our Koi regularly.  And it is not possible to limit the amount eaten by any single Koi when they are fed in a group.  If a group of Koi appear to be "thin," they might benefit from increasing the amount fed at each feeding.  If a single Koi appears thin, it could be genetics, or a health problem, or simply a less aggressive Koi that doesn't enjoy the melee that occurs during feeding.  Most hermaphrodite Koi remain very thin, and sometimes sickly, throughout their lives.

  • 12/07/2017 1:22 PM | Anonymous member (Administrator)

    Ah - the dreaded yellowish looking head...  One of our K.O.I. nutrition students recently asked why some Koi have yellowish skin, rather than pure white.  Here are some of my thoughts about yellowish skin...

    The quality of Koi food DOES matter!  For years, I used cheaper food, and was quite happy with the results.  My Koi never looked perfect, but I just chalked it up to poorer genetics...  Then I started some experimentation with different foods.  I don't currently have any show Koi, so figured I should learn as much as possible with the Koi I have...

    My first experiments started when I was building my monster pond.  I had 12 Koi in a show tank in the basement for 3 years.  I fed them different foods for 6 months at a time, and noted the results.  I discovered that the effects of foods vary considerably!  Koi develop different body shapes, the food affects color, and there is certainly a difference in the amount of waste the Koi produce (poop) depending on the food!  In the 3 years, I put on over 12" of growth on each Koi in less than 400 gallons of water - they grew from about 14" to 26-30"!  That's a LOT of fish in very little water!  I did it with 50% water changes, and blasting the bead filter with 120 psi air for 5 minutes a day.  I learned that biobugs are not easily affected by filter cleaning, and that ShoKoi produced the least waste of any of the foods!  None of the Koi had good whites - and I was told that was because of lack of sunlight - I just had a grow-light over the tank...  Now, I think it had more to do with the food, and the fact that they didn't spawn in the tank...

    Once I got the monster pond up and running, I bought some small Koi, and played with different foods to test growth rates.  The standard food used by most high-end Koi keepers is Saki Hikari.  Every other food is compared to that.  I tried a high end food provided by a breeder - and the Koi didn't like it, plus it was super-oily and did horrible things to my water quality!  I tried Purina Koi feed (Mazuri) - and the Koi had poor body shape and didn't grow properly.  Saki Hikari was OK - sorta middle of the road.  They Koi ate it, and they grew, and they looked OK.  Then this year, I tried a new food just imported in the USA.  Called JPD Shori - there is a another blog article about that food.  Turns out that JPD is the largest producer of Koi food in Japan!  Shori is their premium food.  WOW - huge difference!  The Koi loved it - they now wait in the feeding area an hour before each feeding!  And suddenly, these middle-of-the-road Koi looked AWESOME - you can't believe the difference in the whites - instead of slightly yellow - they were fluorescent white!  Which of course makes all the other colors just shine!  The reds look more intense, the blacks look blacker - even the yellows had more intensity of the pigment.  Go figure!  You never could have convinced me that one factor - food - could make THAT much difference - but it did!  Of course, it could be some combination of my water quality and the food.  Maybe Shori only works with my water quality?  Some of the high-end Koi keepers in my area are going to test it next year, and then we'll know if it's a one-time phenomena, or if it's something that's repeatable in different circumstances.

    As you know, there are LOTS of other things that affect the quality of the white.  The biggest is Nitrates.  If you can keep Nitrates down below 5ppm, then any yellowing of the skin is coming from another problem.  Koi that have been sick, and have compromised liver or kidneys become yellow.  Color foods generally make whites look pink in my experience.  I associate yellows mostly with poor genetics.  When young Koi become mature, and they spawn for the first time, I always find they look better the following year after the spawn.  The eggs and sperm seem to collect unwanted pigment from the rest of the Koi, and once the Koi has spawned, the Koi is left much whiter.  Egg-bound females are almost always yellowish... Water changes seem to have the biggest affect on whites - because of the nitrate reduction.  Plants also reduce nitrates - but somehow, Koi in plant ponds never look as good as those in ponds with massive water changes...  Koi in mud ponds with green water usually have awesome colors - especially red - from all the algae.  Whites can look awesome in mud ponds, or not - I suspect it depends on the water chemistry.  And last, stress really affects how Koi appear...  Some fish stress when you look at them!  LOL  Some have compromised genetics so their organs never grow properly, and they die before they are 6 - meanwhile their whites appear yellow.

    So, if your Koi appear yellowish - go down the list of likely suspects.  Switch to a premium Koi food.  Check nitrates.  If you have anything over 5 ppm Nitrates - do a LOT more water changes...  Did your Koi spawn this year?  If you can check all these boxes, then I'd guess it's just genetics.  You really do have to look at bloodlines when you buy - but the great news is that there are now tons of really good bloodlines, and you can get $30 Koi that have fluorescent white - although they all have plenty of other problems that prevent them from being show fish... 

    I guess that's why this hobby is still so fascinating after 30 years!  There's always something new to learn, and the Koi are incredible teachers!  Experiment with your pond and have FUN leraning!  To me, that's what Koi keeping should be all about!

  • 11/24/2017 8:14 AM | Anonymous member (Administrator)

    1.  Koi originate from Japan and represent love and friendship in Japanese culture.

    2.  Owners who received their Koi as a gift are believed to have good luck.

    3.  In Japan, Koi are often passed down from generation to generation, as a family heirloom.

  • 11/15/2017 7:43 AM | Anonymous member (Administrator)

    Did you know the legend of the waterfall, where a single Koi was rewarded for its perseverance and determination and turned into a dragon?

    One particular legend is the Koi fish’s claim to fame. An ancient tale tells of a huge school of golden Koi swimming upstream the Yellow River in China. Gaining strength by fighting against the current, the school glimmered as they swam together through the river. When they reached a waterfall at the end of the river, many of the Koi turned back, letting the flow of the river carry them away.

    The remaining Koi refused to give up. Leaping from the depths of the river, they attempted to reach the top of the waterfall to no avail. Their efforts caught the attention of local demons, who mocked their efforts and heightened the waterfall out of malice. After a hundred years of jumping, one Koi finally reached the top of the waterfall. The gods recognized the Koi for its perseverance and determination and turned it into a golden dragon, the image of power and strength.

    Symbolism and Meaning

    Koi fish are associated with positive imagery. Because of the dragon legend, they are known as symbols of strength and perseverance, as seen in their determinative struggle upstream. And because of the lone Koi that made it to the top of the waterfall, they are also known as symbols of a destiny fulfilled. Resulting from its bravery in swimming upstream, the Koi is oftentimes associated with Samurai Warriors in Japan. The integrity and high sense of character Koi are known for makes them a popular tattoo choice both in Asia as well as America.

    The Koi is known for its strength, individuality, character, and perseverance.

    Koi fish are also symbolized according to their coloration. Black Koi represent masculinity. It also signifies a patriarchal role. Gold Koi symbolize prosperity and wellbeing in business. Blue Koi, often associated with the role of the son, represents tranquility. Red Koi represent strength and power. It also is recognized as the matriarchal Koi.

    Whatever the legend or color, Koi fish will always carry a positive weight. Whether it be good fortune, longevity, perseverance, or courage, the Koi fish encompasses it all.

  • 11/07/2017 7:04 AM | Anonymous member (Administrator)


    While we may have control over the amount of water we put into our ponds, we don't have control of what's IN that water.  Turns out that many water supplies have been inundated with chemicals from sewage treatment plants.  Wells are also a problem, as chemicals leach into ground water supplies.  This article is about a study that concluded that 1/5th of male fish were transgender or hermaphrodites. A fifth of male fish are now transgender because of chemicals from the contraceptive pill being flushed down household drains, a study by Professor Charles Tyler, of the University of Exeter, has suggested.

    Male river fish are displaying feminised traits and even producing eggs, the study found. Some have reduced sperm quality and display less aggressive and competitive behaviour, which makes them less likely to breed successfully.  The chemicals causing these effects include ingredients in the contraceptive pill, by-products of cleaning agents, plastics and cosmetics, according to the findings. "Many other chemicals that are discharged through sewage treatment works can affect fish, including antidepressant drugs that reduce the natural shyness of some fish species"  says Professor Charles Tyler.

    Professor Tyler presented his findings in a key-note lecture at a symposium where he explained that the offspring of such "transgender" or "intersex" fish can also be more sensitive to the effects of these chemicals in subsequent exposures. Tyler said: "We are showing that some of these chemicals can have much wider health effects on fish that we expected.  "Using specially created transgenic fish that allow us to see responses to these chemicals in the bodies of fish in real time, for example, we have shown that oestrogens found in some plastics affect the valves in the heart." Tests showed 20 per cent of male freshwater fish, such as roach, at 50 sites had feminine characteristics.

    More than 200 chemicals from sewage plants have been identified with oestrogen-like effects and drugs such as antidepressants are also altering fish's natural behaviour, his study found.  Professor Tyler said, "Other research has shown that many other chemicals that are discharged through sewage treatment works can affect fish, including antidepressant drugs that reduce the natural shyness of some fish species, including the way they react to predators,"  Professor Tyler will presented his findings in the opening lecture of the 50th Anniversary Symposium of the Fisheries Society in the British Isles at Exeter University this last July 2017.

    Dr Steve Simpson, who organised the symposium, said the week of talks would gave "fish biologists from around the world a chance to exchange ideas and discuss how to protect dwindling fish populations in rapidly changing seas and rivers, before it is too late.”  Other research discussed at the event includes how the destruction of coral reefs and their distinctive sounds means fish are getting lost in the water, how fish are shrinking because of climate change and how power cables can disrupt how fish find sexual partners.

    From: www.Telegraph.co.uk (link is external) by Sophie Jameson, July 2, 2017

  • 10/26/2017 8:52 AM | Anonymous member (Administrator)


    Santa Clara Valley Koi and Water Garden Club was called in to assist  FEMA / ASPCA  with Koi rescue for the Sonoma Fire victim's koi ponds October 22nd.  We responded . Over 150 Koi have been rescued from these wildfires so far.

    Members donated time and resources to assist by setting up temporary holding tanks and providing equipment and supplies to care the rescued Koi from fire damaged homes and properties that have been brought in by animal services. Some of the most injured Koi have been taken to UC Davis for treatment. 

    Many of the Koi fire victims are being temporarily housed and cared for until they can be returned to their owners or, if needed, adopted in the coming weeks.  As the areas are opened up for residents to return home more Koi are anticipated to be moved to our temporary holding tank facility at the Sonoma Animal Shelter.

    Thank you to our membership,  sponsors, and friends for for caring for these aquatic fire victims in their time of need!   Bless those Koi that didn't make it. 

    If you would like to help support these efforts please send donations to:

    SCVKWG, PO Box 54368, San Jose, CA 95154 

    Please note that your donation is for the Sonoma / Santa Rosa Fire Koi Rescue Project. Donations are tax-deductible.


    Sent by:

     Eve Bretzke

     Webmaster / Newsletter / Membership

    Santa Clara Valley Koi and Water Garden Club

     Email:  info@sckoi.com

     Website: www.sckoi.com

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