Use of Potassium Permanganate to Control External Infections ofOrnamental Fish EDIS FA37

Please use at your own risk.  Know what you're doing before you use KMNO4!  Read this entire document.

Dose Calculator:
http://www.koiphen.com/forums/koicalcs.php?do=calcpp

Stock solution:

1 gallon + 285 grams PP = 2 ppm at 1 ml/10 gallon

1 drop/gallon = 1 ppm
2 drop/gallon = 2 ppm
20 drops = 1 ml
1 ml/10 gallons = 2 ppm (4 hour minimum bath)
5 ml/10 gallons = 10 ppm (30 minute closely watched bath)
10 drops/Gallon = 10 ppm (30 minute closely watched bath)
0.5 ml/gallon = 10 ppm (30 minute closely watched bath)
Neutralize with same volume treated with Hydrogen peroxide 3% USP

Potassium permanganate can also be used as a short-term bath at concentrations of 10 ppm (mg/L) for 30 minutes.

LABEL:

Stock solution Potassium Permanganate KMNO4:
STRONG OXIDIZER NEUTRALIZE WITH H. PEROXIDE
1 gallon + 285 grams PP = 2 ppm at 1 ml/10 gallon
DOSE:
1 drop/gallon = 1 ppm
1 ml/10 gallons = 2 ppm (4 hour minimum bath)
10 drops/Gallon = 10 ppm (30 minute closely watched bath)
0.5 ml/gallon = 10 ppm (30 minute closely watched bath)

FA37

Use of Potassium Permanganate to Control External Infections of Ornamental Fish 1

Ruth Francis-Floyd and RuthEllen Klinger2

1. This document is FA37, one of a series of the Fisheries and Aquatic Sciences Department, Florida Cooperative Extension Service, Institute of Food and

Agricultural Sciences, University of Florida. Original publication date June, 1997. Reviewed July, 2002. Visit the EDIS Web Site at http://edis.ifas.ufl.edu.

. Florida Cooperative Extension Service / Institute of Food and Agricultural

Sciences / University of Florida / Larry R. Arrington, Interim Dean

Introduction

Many disease problems of ornamental fish begin

as external infections. If uncontrolled, the infections

may become systemic, resulting in death of the fish.

Correct use of potassium permanganate can

effectively control many bacterial, parasitic and

fungal agents before systemic infections become

established, often eliminating the need for antibiotic

therapy. The fish owner saves money because use of

expensive antibiotics is decreased, thereby decreasing

the incidence of resistant bacterial strains. In the

ornamental trade, correct use of potassium

permanganate at the onset of an infection can also

speed the movement of fish as they do not need to be

held for lengthy (often 10–14 day) antibiotic

treatments.

What is Potassium Permanganate?

Potassium permanganate (KMnO4) is an

oxidizing agent that has been used for many years in

aquaculture. It is also used in water conditioning

systems and in the plumbing industry. As an

oxidizer, it is able to chemically "burn up" organic

material. This includes undesirable organic matter

such as bacteria, parasites, and fungus, as well as

desirable material such as gill tissue and mucus.

Because the chemical cannot distinguish between

desirable and undesirable organic matter, it is up to

the individual to use the chemical in a manner that

results in maximum benefit and minimum harm to

treated fish.

Color Change Associated with Potassium Permanganate Use

When potassium permanganate is active (in its

unoxidized form), treated water turns a

pinkish-purple color. As the chemical is

"deactivated" (by oxidizing organic material), the

water color changes to yellow or muddy brown. This

color change is an important tool when monitoring

chemical treatment (discussed below); however, this

may make potassium permanganate undesirable for

use in display tanks, exhibits, or ornamental ponds.

As with many chemicals used in water, potassium

permanganate is harmful to plants and invertebrates.

Use of Potassium Permanganate

For most fish, potassium permanganate can be

administered at a concentration of 2 mg/L as a

long-term bath (four-hour minimum) in fresh water

or salt water systems. Potassium permanganate is

also reasonably safe to use in recirculating systems

and has minimal impact on biofilters when used at

2 mg/L. Treated water should retain the purple

coloration for at least four hours.

There is extensive information on the use of

potassium permangante in freshwater systems, but

much less is known about its effect in marine

systems. Fish culturists should run a small bioassay

before treating marine fish.

Some fish, including certain Lake Malawi

cichlids, are sensitive to potassium permanganate and

lower concentrations (1 mg/L) may be safer. A small

experiment run by the authors on a cichlid production

facility in southeast Florida demonstrated that 2 mg/L

KMnO4 for four hours was safe for common cichlids.

The fish owner can determine species sensitivity by

observing the behavior of the fish during treatment.

This is especially important when treating a species

for the first time. If fish react adversely, immediate

action (such as diluting the chemical with fresh

water) should be taken.

Because potassium permanganate is deactivated

by organic matter, it may be necessary to increase the

amount added to ponds or other systems where

organic material has been allowed to accumulate. A

safe way of accomplishing this is to add potassium

permanganate to the system in 2 mg/L increments. If

water color changes from purple to brown in less than

four hours from the start of the first treatment, an

additional 2 mg/L should be added. If a total

application of 6 mg/L potassium permanganate does

not result in maintenance of the purple color for at

least four hours, the system should be cleaned. Most

of the organisms that are treated with potassium

permanganate thrive in an organically rich

environment; therefore, improved sanitation can have

a tremendous impact on treatment efficacy.

Potassium permanganate can also be used as a

short-term bath at concentrations of 10 mg/L for 30

minutes. At this concentration, careful observation of

fish is mandatory to avoid mortality. This is a

convenient treatment when fish are being removed

from ponds and brought into buildings for sorting and

shipping. Following a potassium permanganate

treatment with a low concentration (2–10 ppt) of

salt (sodium chloride) as a semipermanent treatment

for several days or weeks (depending on species

treated), can be beneficial. This combination is

particularly effective in minimizing Columnaris

infections (see UF/IFAS Fact Sheet FA-11,

Columnaris Disease) after handling fish.

Potassium permanganate can be used as a surface

disinfectant at concentrations of 10 mg/L (30–60

minutes contact time) to 500 mg/L (30 seconds

contact time) in a fish room or hatchery, however,

quaternary ammonium compounds are better suited to

this purpose. Potassium permanganate will kill

bacterial, fungal and many parasitic agents, but it is

not viricidal.

Frequency of Treatment

As mentioned above, potassium permanganate is

an indiscriminate oxidizer, and as such, can burn gill

tissue and mucus of treated fish if too much chemical

is applied. A good rule of thumb to prevent excessive

damage to fish is to avoid treating them with

potassium permanganate more than once a week. If a

chemical treatment is needed for a condition that

requires more frequent application, such as treatment

for an outbreak of "Ich" (Ichthyophthirius multifiliis,

see UF/IFAS Extension Circular 920), potassium

permanganate is not a good choice.

Treatment Failure

Poor efficacy following use of potassium

permanganate is usually caused by one of three

factors: (1) incorrect or incomplete diagnosis; (2)

incorrect calculation or measurement of amount of

chemical needed; and (3) excessive organic material

in the system resulting in rapid degradation of the

chemical. Any time treatment failure occurs, sick

fish should be submitted to a diagnostic laboratory for

an accurate diagnosis. Volume of the water treated,

accuracy of calculations to determine treatment rate,

and accurate measurement (by weight) of chemical

used are essential for delivery of an appropriate

chemical dose. As mentioned above, an excessive

Use of Potassium Permanganate to Control External Infections of Ornamental Fish 3

amount of organic matter in the system will result in

rapid deactivation of potassium permanganate, and

therefore contact time with active chemical will be

inadequate for effective treatment. This is often a

problem in heavily stocked ponds.

Determining the Amount of Potassium Permanganate to Use

To calculate the amount of chemical required, a

simple formula can be used:

Amount of Chemical = Volume x

Conversion Factor x Treatment Rate

If the pond or tank volume is measured in

gallons, the conversion factor is 0.0038 and the

answer will be given in grams (see Table 1 for other

conversion factors).

For a treatment rate of 2 mg/L, this formula

would be:

Grams of Chemical = Gallons Treated x

0.0038 x 2 mg/L

Therefore, to treat a 250-gallon vat, the grams of

potassium permanganate needed are:

Grams needed = (250 gal) x (0.0038) x (2

mg/L) = 1.9 grams

An inexpensive gram scale can be obtained by

purchasing a dietary scale at your local grocery store

or pharmacy. One level teaspoon of potassium

permanganate weighs about 7.0 grams.

Table 1. Common Conversion Factors for Use in Calculation

of Amount of Chemical to Use in a Unit Volume of Water for a

Concentration of 1 ppm (1 mg/L).

Units Conversion Factor

grams/gallon 0.0038

pounds/acre-foot 2.72

grams/cubic foot 0.0283

pounds/cubic foot 0.000062

Use of a Stock Solution

An alternative method of measuring potassium

permanganate is to mix a stock solution. A stock

solution is a concentrated solution of chemical from

which small amounts can be taken to treat tanks as

needed. This is useful when either multiple tanks or

multiple treatments are needed. An easy way to

make up a stock solution for potassium permanganate

is to purchase a one-gallon bottle of distilled water,

weigh 285 grams of potassium permanganate, add it

to the solution, and mix thoroughly. This stock

solution will deliver a dose of 1 mg/L when delivered

at a rate of one drop per gallon. Therefore, to achieve

the desired concentration of 2 mg/L, the stock

solution can be delivered at a rate of two drops per

gallon. The stock solution should be stored in a cool,

dark area and be replaced annually.

When treating larger systems, it is useful to

remember that 20 drops are equal to 1 milliliter (ml),

or one cubic centimeter (cc) if measuring the liquid

with a syringe. Therefore, 1 ml of stock solution will

treat ten gallons of water with a concentration of 2

mg/L.

Safety Precautions When Handling

Potassium Permanganate

Potassium permanganate is fairly safe to handle,

however, all chemicals should be treated with respect.

Potassium permanganate will easily stain clothing

and skin. Brown discoloration of skin is not painful,

but it may be unsightly and takes several days to

disappear. Brown stains to clothing can be

permanent. Protective eye wear, gloves and clothing

are recommended when handling potassium

permanganate.

Fish farmers and aquarists do occasionally mix

chemicals. It is important that formalin and

potassium permanganate are NEVER mixed as the

combination can be explosive.

Summary

Potassium permanganate is an oxidizer which

can be used to "disinfect" the external surfaces of

fish. It effectively removes most external parasites,

as well as fungal and bacterial agents. Most fish can

Use of Potassium Permanganate to Control External Infections of Ornamental Fish 4

be treated by prolonged immersion in a 2 mg/L

potassium permanganate solution (water must retain

a purple color for at least four hours), although some

species may be sensitive to it and may not tolerate a

full strength (2 mg/L) bath. Because of its harsh

oxidizing properties, potassium permanganate should

not be applied to fish more frequently than once per

week or mortality may result. It is safe to use in

marine and recirculating systems at 2 mg/L.

Potassium permanganate can stain skin and clothing

so care is suggested when handling it. The chemical

should NEVER be mixed directly with formalin as

an explosion or fire could result.