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Preventative Treatment for New Fish


Preventative Treatment for New Fish

Preventative Treatment for New Fish

Picture of Ben Plonski

Ben Plonski

Ben Plonski, a real lover of koi, has been in the koi business for 43 years. He has been traveling to Japan for 25 years to handpick koi for sale in the U.S. market. He is a member of the Shinkokai All Japan Nishikigoi Promotion Association (U.S. District) and president and co-owner of Laguna Koi Ponds




You just bought a new fish, maybe from our website, maybe from our store or maybe somewhere else entirely. This is a treatment guide designed to keep your new fish and your existing pond fish healthy during the introduction process.

Treat new fish with the following preventive medicines to ensure healthy transition to your pond.

You must know your pond gallons within 10% to be successful.

 Refer to our pond gallon calculation chart for help.

Be certain your pond chemistry is good.

  • Ammonia  0 ppm
  • Nitrite        0 ppm
  • Nitrate less than 100 ppm
  • PH between 7.0 and 8.2
  • Oxygen    above 7 ppm

Do Not Medicate if  water temperature is below 55 degrees.

Medications you will need:

Terminate; FlukeM OR Prazi-Power.

If your pond is less than 3 months established do not use the Terminate in the pond.  This medicine can adversely affect a biofilter that is too small or not fully established.



DAY 1(first day of introducing the new fish):           Treat entire pond with proper dose of both Terminate and FlukeM OR Prazi.

DAY 4:           Treat entire pond with proper dose of Terminate only.

DAY 7:           Treat entire pond with proper dose of both Terminate and FlukeM OR Prazi.

DAY 10:         IF your fish look good, continue with Terminate for one last dose.

This program will control Ich; Flukes; Chilodinella; Anchor Worm and Fish lice.

**FlukeM is a powder and does not mix well with water.  You can mix the FlukeM together with the Terminate in a jar and equal portion of water and shake to dissolve for 30 seconds.

This 10 day treatment will prevent and cure most of your parasitic problems.

If your koi are showing signs of illness (listlessness, rubbing or jumping) after this treatment and your water still tests good, you may have a resistant parasite such as Costia or Trichodina.  You may need to treat the pond with MINN FINN or Potassium Permanganate according to the following directions:

Alternative Pond Treatments



Turn filter off during this bath.

Mix proper dose of Minn Finn Max in a 5 gallon bucket and pour evenly around perimeter of pond and mix evenly with a net.  Good aeration will improve mixing.

After 45 minutes prepare the neutralizer Neu Finn in a 5 gallon bucket.

At the 1 hour mark, pour in the Neu Finn neutralizer around the perimeter of the pond and mix evenly with a net.  Good aeration will improve mixing.  Turn filter back on.

This bath may be repeated again in one week.

Minn Finn 1 hour bath will cure most parasites.  It will also reduce bacterial infection.

Potassium Permanganate.

Potassium Permanganate (PP) is an oxidizer and can kill everything including the fish if not careful.

It can be used as a separate bath or treating the whole pond.

Potassium Permanganate as a BATH:

Tools you will need:

1-Tub or tank large enough to fully cover the koi with water for 50 minutes.

2-Gram Scale.  Do not use teaspoon measurements.

3- Potassium Permanganate.  See dosage below.

4-Koi net to catch the koi.

5-Plastic koi bag to transfer the koi safely to the bath.

6-Small air pump with air diffusers for the bath.

-In a separate tub or tank accurately measure and fill with pond water.

-Add the air diffusers to the bath.

-For every 10 gallons of pond water add 0.3 grams of Potassium Permanganate.  This will achieve 8 ppm.

-Mix and stir the Potassium Permanganate into the tub very vigorously in order to fully dissolve evenly.

-Carefully catch individual koi and scoop into the plastic koi bag to transfer to the bath.

-Cover the tub to prevent jumping.

-Bathe koi in tub for 50 minutes.

-Scoop koi out of the bath with the plastic koi bag and return to the pond.  A little PP in the pond is OK.

Potassium Permanganate (PP) as a whole pond treatment:

Tools you will need:

1-Gram scale.  Do not use teaspoon measurement.

2-A Milliliter measuring device.

3-Five gallon mixing bucket.

4-Koi net or leaf net for stirring.

5-Air pump and air diffusers for oxygen.

6-Potassium Permanganate powder.  See dosage below.

7-Hydrogen Peroxide to terminate the treatment.  Use either 3% Hydrogen Peroxide from pharmacy or 35% Hydrogen Peroxide from Hydroponics store.  BE CAREFUL  35% Hydrogen Peroxide is very dangerous.  See dosage below.

-Measure the gallons of your pond accurately.

-Refrain from adding any Dechlorinator to pond within 48 hours.  Residual Dechlorinator will inactivate the PP.

-Make sure pond has good aeration.  Use air pump and water pump together to increase movement and O2.

-For every 100 gallons of pond water add 3 grams of PP.  This will achieve 8 ppm.

-Mix and stir the Potassium Permanganate into the five gallon bucket first.  Stir very vigorously in the five gallon bucket in order to fully dissolve evenly.

-Once the PP is fully dissolved in the bucket pour slowly and evenly into the pond.

-Use the koi net or leaf net to help stir and spread the PP evenly in the pond.  Use the five gallon bucket to help stir and mix evenly into the pond.  Water should be very purple color.

-Bathe koi for 45 minutes.

-TERMINATE the treatment at 45 minutes with proper dose of Hydrogen Peroxide.  See dosage below.



If using 3% Hydrogen Peroxide from pharmacy, add 3 ounces (100 mls) per 100 gallons.

If using 35% Hydrogen Peroxide from Hydroponics store, add 0.3 ounces (10 mls) per 100 gallons.

-Mix the Hydrogen Peroxide into the five gallon bucket with water first to dilute.

-Spread and mix evenly into the pond in order to fully distribute and terminate the treatment.

-The water will turn form purple to a tan color within 5 to 10 minutes.  Tan color means it is terminated.

-Add another 25 mls of 3% Hydrogen Peroxide or 2.5 mls of 35% Hydrogen Peroxide per 100 gallons every 5 minutes in order to turn the tan color back to clear water.

DO NOT OVERDOSE WITH HYDROGEN PEROXIDE.  This will burn the koi if overdosed!

Repeat the above treatment again in one week.  This treatment will kill Flukes, Costia, Trichodina, Ich, Chilodinella, Anchor Worm and Fish Lice.  However multiple weekly treatments may be necessary to kill the life cycle of some of these parasites.  Treating with this 8ppm dose in the pond is very dangerous to the fish.  If you overdose or cannot terminate properly you can kill your fish with the Potassium Permanganate or the Hydrogen Peroxide.

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