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Koi Health

Taking Care of Koi Fish:

Taking care of koi fish is not as hard as it seems. However, it does come with its fair share of challenges. When you are first starting out, one of the most important keys to raising healthy Koi is water quality and making sure that the water is balanced and aerated properly. In addition to that, also having the right details about koi feeding, health, and handling is just as important as having good water parameters. All of these components are vital and will play a part in the life of your koi 


In order to help our customers, we have provided a guide that will help you properly raise your koi into the beautiful living gems they are meant to be. In this guide, we will provide you with different tips on quarantining, feeding, maintaining water quality, and basic pond care.


At Artisan Koi Farm, we understand that raising koi is an exciting and fun hobby, but we also know that raising koi should also be done carefully. Using this guide, we hope that we can provide you with the necessary information to give your koi the happiest life possible.


Quarantining Your Koi and Its Importance:

A Quarantine tank is an important tool for both koi hobbyists as well as koi breeders. By utilizing a quarantine tank, you can prevent the spread of parasites, bacteria, fungus and other various health issue. Whenever you receive new koi, regardless of where you got them, we recommend that you quarantine your new fish for at least 2-3 weeks. More often than not, these new koi may still carry illnesses, even through our efforts to check. By quarantining your fish, you can make sure that these illness don’t spread to your home pond. Also another thing to keep in mind is that whenever a koi is shipped, they are more than likely to be stressed and exhausted. They are very similar to how people are  is when they have traveled for a long time. Because of this, it is important for you to give them a proper place to rest.


At our farm, we have found that quarantining tanks are the best way to decrease the spread of diseases.  By isolating your koi in a tank, you can not only prevent the spread of diseases but also safely diagnose the problem without risking the health of your already healthy koi.


Even if you have bought your koi from a highly trusted supplier, we highly recommend every customer to quarantine their fish. To help you begin quarantining , we will provide the basic supplies you will need below:


  • Tank

  • Net to cover the tank

  • Small filter and pump

  • Air pump

  • Test kit: ammonia, nitrite, pH and salt

  • Salt

  • Water thermometer

  • Fresh dechlorinated water, existing pond water, or well water.

  • Heater


Setting Up a Quarantine Tank for New and Existing Koi:


1. When customers are setting their quarantine tank, we recommend a 100-300 gallon tank as it would be ideal for most Koi. 


2. The next step is to fill the tank with water, making sure to fill the tank with your pond water or fresh dechlorinated water.


3. Now that you have water in your tank, make sure that the water temperature is at 72 F or above. If you only have a small tub/tank then using two aquarium heaters should be acceptable.


4. While you are setting the tank up, keep in mind that a proper filtration system is recommended. If you don’t have a filter, an air pump  should work just fine.


5, In terms of salt, we recommend 0.3%  salt concentration for all of our quarantine tanks. Please note, if you have not added koi into your pond over a year, then we recommend a 0.05% salt concentration). 


Factors When Raising & Caring For Koi:

When you are raising koi, feeding, water quality and health control are the three important points that every koi owner should have in mind. Although koi are hardy fish, easy to take care of, and adaptable, they still need to be taken care of daily. 


Feeding Your Koi:

When it comes to feeding your koi, keep in mind that koi may typically consume everything that is presented to them. As long as it is not a threat to their safety, be prepared for them to eat it. This however, does not mean you should give them whatever you have to feed them.  Also, please remember that koi will continue to eat despite being full. They are capable of eating so much so that they can develop an illnesses. To prevent this from happening, be aware of how much you are feeding them.


We recommend our customers to feed your koi an amount that will allow them to finish within a five to ten minute period. Any more than that, and you are overfeeding. If they finish their food faster than five minutes then your underfeeding. Put simply, it all comes down to finding the right balance. Once you know how much to feed your koi, we recommend you feed them every 3-4 hours.


One of the most wonderful things about koi, are their magnificent colors. By providing them with the right food, you are giving them the best opportunity to grow and enhance their size. When it comes to koi food, there are a lot of varieties on the market. Each one has its benefits. Some pellets may help koi grow specifically while others focus on color enhancement. There are different foods for every aspect of koi. At our farm, we focus solely on color enhancement and growth.


To find out what food we use visit {Koi Food}.


Tips For Keeping Your Water Quality Under Control:

To keep your water quality at its very best, there are two main focuses every koi breeder should remember. The two components are called aeration and filtration. 


Koi’s excrete urine and produce feces, and ammonia is excreted through the gills. Alongside the ammonia, various other debris and waste such as leaves can collect in ponds and slowly decay. The job of filtration is to remove these wastes and any impurities that remain in your pond. This will not only prevent sickness from occurring but also create a comfortable living environment for your koi. 


Another aspect of water quality that needs to be mentioned is sufficient aeration for your koi. The amount of dissolved oxygen in the water needs to be controlled by an air pump. This is vital because if your water is lacking of oxygen, it could be fatal. A tip you can keep in mind is that when you see your koi’s gather up at the surface for air, there is a probability that that your pond is lacking sufficient oxygen.


Checking Your Water Quality:

To properly check your water parameters, we recommend our customers purchase a water test kit. If you are in need of one, they are available at most pet shops near you. These test kits usually come with several glass test tubes with different solutions that will allow you to see exactly what is in your water. Some of the chemicals these kits test for are:


  • PH

  • Ammonia 

  • Nitrite 

  • Phosphate


To keep things simple, we will provide the numbers we strive for in our waters in order to keep our fish happy and healthy.


  • PH- pH is a measure of hydrogen ions to hydroxyl ions. The ratio is measured on a scale of from 0 (acidic) to 14 (alkaline). Most tap water is around 7.0-7.6. This ratio is ideal for koi as they do best in water at 7.0 to 8.0. Please note that Koi can usually tolerate a wide range of Ph level from 6.0 all the way to 9.0. What they can’t handle, is a rapid change of Ph. What we recommend is that the Ph level should not change more than 0.2 per hour. An acceptable level of Ph is anywhere around 7.0 - 8.5.


  • Ammonia-When fish eat food, they produce ammonia as waste. If your pond is experiencing high levels of ammonia, it can burn the gills of the fish. If the gills of the fish are burned, it reduces the ability of the fish to release the ammonia. Instead, the fish will hold the ammonia inside their bodies, thus leading to death. Even at lower levels, ammonia can create health problems such as stress. It can even lower their ability to fight off bacteria and illnesses. For this exact reason, an acceptable ammonia level should always be 0. 


  • Nitrite-If you find high nitrite levels in your water, we recommend that you do a water change, stop feeding, and add oxygen. Whenever high nitrites occur, it can often cause diseases. One common signs of high nitrite is when your koi are staying at the surface of the water, gasping for air. Like ammonia, the best way to lower nitrite is to perform water changes. We recommend keeping nitrite at 0.


  • Phosphates- Phosphates is created when the element phosphorus is bounded with oxygen and other minerals. When you find high levels of phosphates in your pond, it can be the leading cause of algae blooms. If you the phosphate levels are low, algae growth decreases. 


  • To prevent high levels of phosphates, make sure to use high quality koi food as some foods contain high amounts of phosphorus. A tip we have is to check the labels on your koi feed, sometimes the manufacture may label the amounts of phosphorus in the used. If there is a label, we recommend koi food that contain less than 1% of phosphorus. Another tip is to maintain your filtration system. By doing this, you can prevent phosphates from leeching into your pond, as they often attach to fine particles found in your filter as well as your pond. An ideal phosphate levels around is 0.005 ppm.


Daily Monitoring:

One of the most common ways to see if your koi is healthy, is by reading their body language. Most of the time, your koi will tell you how they are feeling. If you see your koi swimming around your freely, there is a good chance that it’s healthy. Another quick tip for checking if your koi is healthy, is seeing whether they rush over to you when its feeding time. 


Like humans, koi can become ill, especially if they are not taken care of properly. A way you can tell whether your koi is sick, is by checking whether your koi is stationary or isn’t move around as much. In many cases, your koi may even be hyperactive.


Some symptoms of sick koi include:


  • Lying upside down on the bottom of your pond

  • Color of the scales are fading

  • Hyper energetic or jumpy behaviors

  • Little to no movement

  • Refuses to eat



Please note: Koi usually sleep around nighttime so don’t confuse a sick koi and a sleeping koi. Around nighttime, koi will remain at the bottom where they rest. And in the winters, koi will hibernate through a process called torpor. This is a when the koi is in a state of decreased physiological activity. This is usually caused by a reduce body temperature and metabolic rate. This is completely normal and is nature's way for your koi to become acclimated to the cold.


Our Promise:

At Artisan Koi Farm, we take the health of our koi very seriously and it is our promise to deliver you our best and most high-quality koi available. In doing so, we know that raising koi is a fun and exciting endeavor, but we also know that it takes effort to keep them healthy. In order to help our customers and new hobbyist, we have created this thread to help you along your journey. We hope that this koi health guide has been of help to you in some way. If you have any more questions regarding koi health, please feel free to email us at For more information, view our FAQs

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