Every so often, you will come across a Koi that you can’t resist and just have to buy, but how do you know that this fish isn’t carrying harmful diseases that could spread to your other Koi? It’s very important to make sure all new fish are disease free before adding them to your pond, quarantining fish is the best way to prevent outbreaks from occurring in your pond & of course to make sure the new Koi can be seamlessly add to the pond without problems. Most of us are guilty of (BTA) being too anxious, to put that new Koi in our ponds. It’s possible and often works fine to add a new fish to a pond containing other fish without problems. But that’s not always the case. Adapting a new Koi is not always simple process. When you purchase a new Koi, you’re asking it to adapt to new life in your pond. No two ponds alike, every pond has it’s own unique DNA water quality wise, the difference in water from pond to pond effect Koi, this is a big change, Koi do like change, change stresses Koi, stressed Koi get sick & sometime die.

Moving Koi can be stressful and dangerous, they can experience what is called chemical shock, every pond has what is called background pollution, which might not affect your current stock of fish, but might adversely affect a new fish. That’s why you never want to just throw a new fish into your pond.

We usually talk about quarantining because the new Koi might have a disease, but an equally important reason is to make sure the new Koi doesn’t get sick from your pond. To survive it needs to be properly acclimated to live in your pond.

In the process of receiving a new Koi a lot of stressful thing happen.

  • Chase & netted (stressor)
  • Put in a bag in small amount of water. “stressor”
  • Transported, up to 36 hours, with a lot of motion. “stressor”
  • Temperature change. Up 15 deg in 24 hour period. “stressor”
  • Moved to different body water, with different water parameters. “stressor”

All these stressful things will definitely lower the Koi immune system. Now we have scared, traumatize Koi; we want to fit seamlessly into our pond. Keep in mind your new Koi may be at its weakest state on arrival to their new home, so great care must be taken to give them conditions in which they can recuperate fully, failure to do so can push them over the edge.

I think we clearly understand we need to quarantine all new Koi; question now comes up how to do it right.

First, besides a clean bare tank without gravel or rocks, what other things do you need to quarantine my new Koi?

Fully cycled biological filter, thermometer, heater, air pump with air stone, net to cover the tank, a canary fish, test kit, and really good water, because the most common cause of non-infectious disease in Koi is poor water quality.

Upon arrival what is the most important things a new Koi needs?

Prime quality water and rest, give it time to recover from the stress of handing, moving and transport, this allows it to help gets it’s immune system back to optimal level, it also allows Koi to regain its defense again sickness and disease. Stay away from the Koi as much as possible the 1st 24 hours, give the Koi something to hide under like piece of Styrofoam or plastic garbage can lid, it will help the Koi feel secure and help it calm down making it less likely to jump.

What is proper procedure to remove Koi from the bag?

Newly arrived fish will come to you in an oxygenated plastic bag, after a quick inspection; float the bag 20 to 30 min to equalize the temperature. Inside this sealed transport bag the Koi are expelling carbon dioxide, witch sets off chain reaction that causes the ph to drop this makes the ammonia in the bag less toxic, but when you open this sealed plastic bag the carbon dioxide starts to escape causing the ph to rise very quickly, making the ammonia instantly toxic to the fish. Once you open bag get the Koi out of the bag as “ASAP”.

Net: new Koi always frighten and disorientated, their first reaction is to jump, why? It’s their attempt to flee unfamiliar surrounding. Always net you Q-tank and make sure the net is tightly attached.

Should I use salt in my quarantine tank?

Salt has been referred to as chicken soup for Koi and gold fish, salt helps Koi overcome stress, helps to fight nitrite toxicity and kill many parasites, help heal the slim coat, makes it easier for the Koi to maintain it’s osmotic balance. According to Erik Johnson D.V.M. in his book “Koi health and disease” salt kills 7 out of 9 parasites. Negatives; if there is a specific problem you want to treat be aware there are some medications salt cannot be used with.

Parasite treatment

  • Proform C; will treat Trichodina, Costia, Chilodonella, Ich, oodinium & fungal infections.
  • Praziquantel; treats Flukes.
  • Cyropro; treats anchor worms & fish lice
  • Ulcer aid RX; treats body sores, fin & mouth rot, gill infections

Why you should not quarantine a Koi by itself?

Koi are social, theirs much happier with companions in their tank, it helps to calm the Koi down and helps relieve stress. Plus by adding I or 2 fish from your pond to the quarantine tank, These canaries fish will gradually introduce your pond’s unique signature to the new Koi in the quarantine tank and vice versa, plus, this is a good way to check to see if the new fish are carrying any ‘bugs’ that might cause a problem with your fish collection. (Make sure your canary Koi are Koi you don’t mind losing if something goes wrong)

How to feed your Koi during the quarantine period.

Don’t feed high protein food, unless have a really good filter on your quarantine system, because it will produced more waste, Feed highly digestible wheat germ food. Not necessary feed several times a day.

Remember you are not trying to grow them in your quarantine tank and providing really good water quality is much more important than a lot food.

Water changes during the quarantine period.

Infrequent water changes can allow ammonia levels to spike, plus the respiration of the Koi causes a build up of carbonic acid and organic acid from metabolism causing low ph, in addition there are minerals, essential & nonessential that Koi absorbed from the water through the gills, these minerals can only be replaced thru water changes. Optimal water quality is a must. You can put a perfectly healthy fish into water with elevated ammonia or nitrite levels and it will become stressed and most likely sick in a short time. When adding water keep in mind that chlorine and or chloramines is in your local water supply so use a de-chlorinator to neutralize them. If you have good filtration system 10 to 15 % a week is fine, if not, you may need to make up to 50% water change per day and use an ammonia remover.

How long should the quarantine period last?

Koi should be kept in the QT for a min of 21 days. 30 to 45 days better this is a case where longer is better, because it takes about 4 weeks to accomplish a really thorough quarantine process. The word quarantine itself, means 40 days of isolation.

Why do you need really good aeration?

Oxygen plays important role in keeping your Koi happy & healthy, Fish will succumb faster without oxygen than they will in water with high ammonia or nitrite levels, the bacteria in your biological filter need adequate oxygen to carry out the nitrogen cycle, low oxygen levels will greatly increase stress, remember stress fish get sick.

Why do you need a heater & thermometer in your quarantine tank?

Idea temperature range for Koi to heal is 72 to 78 degrees, that is where the Koi immune system is at it’s best. Another reason want temperature between 72 to 78 degrees is because some viruses only appear when the water heats up, you want these viruses to manifest themselves in the Q-tank, one such viruses is the dreaded KHV (Koi herpes virus). KHV is a deadly disease that can hide inside a fish that appears healthy, it is temperature dependent and only replicates and causes disease in a narrow temperature range between 70 & 83 degrees, so it’s critical to quarantine in the middle of that range about 73 to 78 degrees. If all goes well after about 3 to 4 weeks you Koi is most likely fine.

Why should you always quarantine new Koi inside?

Having Q-tank inside makes it easier observe for problems in case a problem occurs easier to detect and treat, plus it cheaper to treat than treating your whole pond. Easier to maintain, water temperature & quality of the water. Won’t have to worry about frogs, birds or raccoons cross contaminating your pond. FYI; if you keep your tank in your garage and you store gasoline, paint or other chemicals, close your eyes and do the smell test, if you can smell gasoline or paint fumes so will your fish, the aeration pump will transfer those fumes into your water. These canaries were a protection, the canary fish play the same roll they gradually introduce your pond’s unique signature to the new Koi in the quarantine tank and vice versa. Plus, this is a good way to check to see if the new fish are carrying any ‘bugs’ that might cause a problem with your fish collection.

How big should your quarantine tank be?

Quarantine tank can be as small as 100 gals of water; the problem with small tanks, temperature, ammonia, water parameters in general, can change quickly in a small volume of water. The smaller the tank less margin for error. This is case where bigger is better. While 100 gallons can be your starting point, if you have the room 300 to 1000 gallons is much better. Whatever the size, must be large enough to hold the new fish. Need to know exactly how much water in case you need to medicate. Some meds kill rate in slightly above the cure rate.

Test kit

Because, the naked eye cannot tell the condition of the water even if it’s clear. As stated earlier you want condition in the Q-Tank to be as stable as in possible. Need to check water parameters every day, remember dealing with small quantity of water means water parameters can change very quickly.

What is the last thing to do before adding a new Koi to your pond?

After the Koi has been thru the quarantine period & recovered from the stress of being moved, you need to get the Koi ready for your pond by adding water from your pond to the quarantine tank, this will help to prevent the Koi from being adversely affected by back ground pollution when it enters your pond. Never interchange equipment btw main pond & quarantine system. Best to have separate set of equipment or at very lease sterilize it. The quarantine and treatment of new fish is probably the single most important thing Koi owners needs to do to ensure the health of their ponds and fish. Remember what you do or don’t do will often determine how well that new Koi adepts to your pond.

Having a suitable quarantine tank is part of proper Koi care.

As a review these are the 4 goals we want to achieve during the quarantine process, reduce the stress of the new fish, evaluate the overall health and condition of the Koi, treat the fish as required and prepare the fish for it new home in your pond.

It is estimated only 5% of Koi keepers; quarantine new Koi, which means 95% don’t, are you among the 95%???