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1. check the water parameters: pH,  ammonia, nitrite, nitrates
2. do the fish physical
3. change some or all of the water
4. from the water parameters and physical decide on a course of action
5. if there is nothing specific, do the tub to tub method

1. When ever a fish is showing symptoms or a change in patterns of swimming, resting, etc. suspect toxins, either sudden ammonia spike, spray aerosol, in ponds aerial spraying for bugs.  Start with a big water change and increase aeration.  See if they perk up.  If they don't in a couple hours, try moving them into a 5 gallon  bucket of freshly aged water with an airstone but no filter for 24 hours. MAKE SURE THE TEMPERATURE OF THE OLD AND NEW WATER IS THE SAME.

The quality of the water is essential. Both city water and well water can change rather suddenly.  If the taste or smell of the water coming out of the tap seems different, it probably is.  If you won't drink the water out of the tap,  then the water isn't good enough for your goldfish.

When water testing parameters are fine, the filter is clean, the water changes have been right on schedule, but the fish are still having chronic problems, then the tap water is most likely to blame.  You will need to contact the city and find out what is being put in the water.

Aging water with an air stone and using a water conditioner (like NovAqua which precipitates metals) is the best way of getting rid of a lot of possible toxins.  A big garbage can be stored anywhere, brought in, filled with water, aged overnight, pumped out with a small pump into the tanks the next day and then moved out of the way. Be sure to use only the top 2/3 of the water in the tank.

2. Perform the fish physical paying special attention to the color of the gills.  If the gills are dark red or glopped together, if the fish have been gasping at the surface, even a salt dip might kill the fish.

3. If the gills are bright red, the next thing to try is a quick salt dip, like 30 seconds and into a 5 gallon  bucket of freshly aged water with an airstone.  See if they perk up in 24 hours.

4. The last thing to try is meds.  I like to compare the diagnosis and treatment of fish to picking and eating wild mushrooms. If I am not, absolutely  dead-bang sure what the mushroom is, I don't eat em.   If I am not sure what the problem is with a fish, treating them with medications is more likely to harm than help.

Change some water, 25 - 30%.  Test the water parameters first of course.

Put in a little salt. Start with 1 teaspoon per 5 gallon and up to 1 tablespoon per 5 gallons of water of rock salt with no additives. Solar salt used for water softeners is the best since it has trace minerals in it.

Topical treatments of spots, dots, wounds with peroxide and Neosporin or Panalog

1. Do not treat near the gills, eyes or mouth with peroxide, however, neosporin can be used except directly on the gills.
2. Assemble everything within easy reaching distance of the tank.  Tissue, swab in a capful of peroxide.  Tube open.
3.  Wet both hands.  If right handed, pick fish up in left hand and use the right hand to position the part of the fish with the wound above the water.  Try to point the head down t keep one set of gills in the water.
The head down and eyes covered quiets the fish.  Working over the tank ensures that in case the fish wiggles loose, it will splash down, not thud.
4. Dab the sore with tissue to dry the area then dab the area with peroxide, wait 5 seconds and dab dry.  Now put a dab of Neosporin or Panalog CREME on the area and rub it in for a couple seconds.  Release the fish.  Do not be concerned if some of the creme comes off or the fish eat it.  It wont hurt them.  Only treat with the peroxide once, but the creme can be used up to three times a day.
*** mercurochrome or merthiolate can be used instead of peroxide.  Again, do not get it near eyes, mouth or gills.

Quick Cure and PP, even when used at recommended dose and for recommended times is hard on the gills, lets say a 3 or 4 on the toxicity scale. If the actual problem is water quality and the fishes gills are already toxed or burned (look dark red), adding QC or PP could further damage the damaged gills and kill the fish.  Remember, once treatment is begun with one medication  it can shut the door on using the correct medication specific for the disease or problem for a couple weeks or more.

Contains formaldehyde and malachite green.  It is used for 3 days with 30% water changes each day. Since light inactivates the malachite, add it and turn off the lights after observing them for 15 minutes.  Always have a gallon bucket of the tank water handy in case of bad reactions (first 15 minutes or so).
CAUTIONS: FORMALDEHYDE CONTAINING MEDICATIONS MUST NEVER BE REFRIGERATED.  This causes a precipitate called paraformaldehyde that is deadly to fish.  Para makes the solution look cloudy, but if there is only a chance that paraformaldehyde has formed, dont use it.
Formaldehyde medications should not be used to treat fish if the water is below 60oF.

3.  Stress lowers the immune system.  Fish live in a balance with pathogens.  When healthy, their immune systems can keep a few, lingering bad bugs in a suppressed state.  Sudden changes to the environment, pH, temperature, changes in water quality, handling, changes in population can and do cause stress.  All medications and treatments also cause stress in fish.  If the medication doesn't actually treat the disease, it will simply compound the stress on the immune system making it that more unlikely that the fish will be able to fight the disease successfully.

4. In general, combining different medications in the water must be considered unsafe because it compounds the stress on the fish. This is also true for using different medications one after another within a short period of time.  It is important to be sure of the diagnosis before treatment is started. Once that medication is put into the water, it shuts the door on other treatment possibilities for a number of days. This is especially important if there are multiple problems or disease resistant pathogens involved.

All medications that can be used as dips are safer being used as dips. When putting medication in tank water, have a bucket of the tank water sitting by in case the fish has a bad reaction.  Some water conditioners inactivate some medication.  NovAqua and PolyAqua is VERY good at inactivating metals and promptly inactivates potassium permanganate.

5. Pet store advice. Beware!! How much experience do they have?  Do they have the best treatments like potassium permanganate, formaldehyde and malachite green available? Do not use medications that have not been specifically tested for use with goldfish. You wouldn't give a cat aspirin even though it is useful for humans and dogs.

Many of the OTC (over the counter) medications sold in LFS (local fish stores) are in too low a concentration to be useful, or contain materials that are potentially very toxic for GF.  For example, Aloe vera is highly useful for many animals but preparations that use the outer skin of the plant "leaves" contain saponins which are not good for GF.

According to those cited in Noga,  the main ingredient in Fluke Tabs (mebendazole) is not effective against Dacs, one of the two main kinds of flukes.  He reports that "there is considerable species variation in responses" to the mediation which means that some fish react badly ... it has not been extensively tested for use with goldfish or carp and there are reports of gill disintegration with its use."

So even when medications are used on other fish and are safe, this does not mean their use with Koi/carp/or GF is safe and fish in ponds can react differently than GF in tanks.

Differences in pH, hardness and temp seriously changes how toxic/effective different medications are.  In general, the more acid and softer the water, the more toxic meds are going to be.  The more extreme the temps, very hot/cold, the more ineffective/toxic the meds will be.


Gyrodactylus (flukes)
Other external parasites and bacteria, but not the treatment of choice for ich.
Topical treatment
Sterilizing tanks
Inactivating hydrogen sulfide while cleaning gravel or ponds
Reducing organic load in ponds
Treatment of plants before putting into tanks

Powerful oxidizer.  Unlikely that organisms can become resistant.

It is one of the least toxic treatments.  Salt dips are considered less toxic.
PP is toxic in water with a high pH since PP may precipitate out into the gills.
It should not be used in sea water tanks.
It should not be mixed with formalin.

Drugstores: 4 oz is usually sold.  Add this to 1 quart of water (distilled is better)  = stock solution
Water softening companies: 1 lb in 1 gallon of water = stock solution
Farm supply stores
Local chemical supply houses
Fishy Pharmacy: 1 lb containers. Must be shipped as hazardous materials. 1-800-423-2035
Preparation: see caution below

** Dechlor will inactivate PP.  Other water treatments may inactivate PP as well.  If  PP does not remain pink either use PP as a dip or use bottled water, or, use water aged for 24 to 48 hours.
1 drop of stock PP per gallon is equal to 2 ppm.  This is the concentration used for continuous treatment.  PP is usually used for 3 days, or every other day for 4 treatments.  If water is not clear in 24 hours (looks yellow), change 25-30% of the water before adding another dose. Light inactivates PP.  After adding the PP,  watch for a minimum of 15 minutes to make sure there are no adverse reaction.  Then turn off lights or cover the tank.
Some water seems to inactivate PP rapidly.  It should be pink when you put it in, and stay pink for at least 4 hours to be effective. Noga recommends at least 8 hours.  If it is quickly inactivated, move fish to a bucket of same temp fresh water and try again. If the PP still decolorizes too quickly, it may be necessary to add more than 2 ppm of the PP to keep the water pink.  Experimentally find this dose by drawing a gallon of water to be treated and without fish, add up to 4 drops of the PP and see if it remains pink overnight.  If the water still does not hold the color, a bath may be the only option.  Heavy algae on tank walls, heavily loaded filters or gravel will react and decolorize PP.
Jo Ann Burke uses a capful of hydrogen peroxide (0.3%) precipitate inactivated (brown) PP in a 20 gallon tank.

Use for 30-60 minutes at twice the normal dose. The tank can be drawn down 50%, the PP added and then refilled with fresh water the bath treatment is done.  Be sure to have the bucket of untreated tank water sitting next to the tank in case of adverse reactions.

Stock PP can be used on a swab on small wounds or patches of white "crud" on fins.  It results in a chemical burn and turns the area dark.  Do not use near the eyes, mouth or gills.  Use as a one time application, followed by Neosporin creme or Panalog (by vet prescription).  Hydrogen peroxide is preferred for topical application.

This is done with no fish or other live things in the tank.  Remove air stones.  Clean the tank and filters.  Put enough PP in so that the water is purple and let the filter circulate for 24 hours. Put in a capful or more of peroxide.  Clean the filters after a couple of hours and wipe down the tank walls.

Start with 1 drop per 2 gallons of water (1ppm).  When light pink turns yellow, add more PP, 1 drop per 2 gallons, up to 3 drops per gallon (6 ppm).  If pond/tank is yellow after adding 6 ppm, stop cleaning and either do a water change or remove the fish before continuing the cleaning.

Start with 1 drop per gallon (20 drops per ml, 1 ml per 20 gallons).  If water turns yellow in less than 15 minutes, add up to 3 drops (6 ppm).  Do not do this if the pond has a  high pH.

No idea what works here or which plants could be harmed.  More information/experience is requested from those who have done this.

1. Potassium permanganate crystals must be handled with care.  It should not be inhaled as it is toxic to lungs.  For this reason, it is a good idea to wear a mask when handling the crystals.  Using a funnel, slowly pour the amount of crystals to be used into a dark container (either brown glass or plastic wrapped in tin foil since light inactivates PP). Slowly add water half way, cap and turn the bottle over to wet thoroughly.  Fill the bottle to bring it to the correct volume.  For a quart of stock solution, a whole quart of water will not be needed. Stock solution of PP is safe to handle, although it will oxidize your skin if it comes in contact.  PP was used as an antifungal remedy for athletes foot only a few years ago.  The toxicity is when the crystals get airborne and into the lungs. Wear a mask when handling the dry crystals. Wear gloves when handling the stock solution.  The stock solution must be mixed (bottle turned upside down several times) right before use. Do this over the sink with running water and rinse the outside of the bottle before and after opening.  Stock PP stains clothing permanently, and everything else if not wiped up immediately.

2. PP is good for removing organic crud (or algae) in a pond or tank, but then the crud starts breaking down and polluting the tank. It is necessary to clean the filters after the water has cleared.  Continuous treatment levels do not harm established biofilters.  PP will oxidize the outer layers of algae in the tank.  A light cleaning of the tank walls will expose the live algae underneath.

3. I once added PP to a tank with too much organics and "something" toxic was given off.  I had to quickly remove 1 fish to fresh water. Always have a gallon of the tank water in a separate container drawn from the tank before adding anything to a tank,  just in case fish have a bad reaction, there is someplace to put them quickly.

4. Hydrogen peroxide will oxidize and clear the PP out of a tank in a couple of minutes.  However, PP forms a precipitate that could irritate the gills of fish. If the fish are already having problems with oxygen uptake, adding the peroxide is not a good idea while the water is pink. High pH water will also precipitate the PP out of solution.

About potassium permanganate:
You must also be very careful of the pH when using this, if it is too high you will precipitate out tiny manganese oxide salts which will plug the fishes gills and could kill them.  Oxidation of the "organics"  will lead to carbon monoxide production among other things. Also a number of carboxylic acids, any of these will do in your fish if they get enough, as with any poison. Jonathan  (who is a chemist)


Laguna Koi Ponds
   20452 Laguna Canyon Road
   Laguna Beach, Ca. 92651

   From their 1996 catalog "TRICHLORACIDE- Synonyms Dylox, Dipterex and Masoten.  An organophosphate compound effective against external infestations.  Treats fish louse (Argulus), anchor worm (Lernea) and gill and body flukes (Trematodes).  Be extremely careful when handling, VERY TOXIC.  Disperse evenly throughout pond.  Temperature and pH dependent; requires four or more successive treatments. 100 grams treats 4500 gallons -----$9.95  End quote.  A good little
catalog to have on hand.


reprinted with the permission of Rod Farlee
USDA publication 410, Table 3, recommends 200 to 500 ppm salinity (1-1/2 to 4 measuring teaspoons per 10 gallons) as an indefinite treatment to reduce stress.

Salinity eases osmoregulation in freshwater fish.  The precise amount isn't important, because their response is logarithmic.  In other words, the change from no added salinity (most tap water is less than 10 ppm) to 200 ppm is large, compared to the further increase to 500 ppm. This salinity is also more than adequate to prevent nitrite toxicity,  and is below the level that will affect aquatic plants.

To learn more about:
  salt to prevent nitrite toxicity:

  salinity and electrolytes: page 4 of:

  osmoregulation in fish:,5716,120748+6+111049,00.html

  salt for biofilter bacteria: see Table 3 on page 5 of:

  calculating how much salt to use:

- Rod Farlee

Fish cells are saltier on the inside than the fresh water outside. When there is unequal concentrations of salts, the area with higher salts will lose salt to the area with lower salts. At the same time,  water will move from the area of lower salts into the area of higher salts to dilute the salts.  This is called osmosis.   It is the reason that blood on clothes is removed by soaking in plain water ... it lyses the blood cells and dilutes the iron out of the cloth.
All animals that live in fresh water have to expend energy to hang onto their salts AND to keep the fresh water out.  Most of the fresh water fish can no longer deal with "salt water" conditions (altho ocean going salmon can go back and forth from salt to fresh water).
But adding some salt to the tank water lowers this energy expenditure. Salt also does one other thing, it stimulates the production of slime.  Fish dont have much in the way of antibody, but they do have a secretory kind that is added to the slime coat where it reacts with parasites.  But having a continuous production of slime,  parasites have a harder time getting to the skin of the fish and shedding of the slime coat sheds many of the parasites as well.  Normally, healthy fish are resistant to even pathogenic strains of bacteria.  However, fish suffering mechanical damage from handling or spawning that removes the slime coat and/or opens a wound, those that have a primary infestation with a parasite that opens the slime coat and punctures the skin of the fish and when water quality/oxygen levels/temperature are so poor that the immune system of the fish is dysfunctional or there are infected fish shedding large numbers of bacteria in the pond can result in bacterial infection.

What salt dips do:
1.  Helps fish that have been shipped recover their electrolytes
2. Strip off the slime coat and chemically knock off a lot of parasites.. it seems to be more of a shock to parasites than the fish
3. A fish that has been dipped is more susceptible to medications once the slime coat protectant is gone AND  the remaining parasites are exposed to medications.

What low concentrations of salt does:
1. Provide needed minerals (if solar salt is used)
2. Stimulates slime coat production.  Fish have antibodies and other anti microbial agents which are excreted into the slime coat where they bind to parasites.
3. Appears to protect fish against nitrite poisoning

Percent (%) is a measure of the number of grams of a chemical per 100 ml of water.  So 0.3% salt solution means there is 0.3 grams of salt per 100 ml of water.
THIS HAS NOTHING TO DO WITH WHAT IS READ ON A SALT METER - please read the instruction manual that comes with the meter to translate what the METER says with what the concentration is in percent (%)

A solution of one teaspoon per gallon is 0.132% salt. So 1 tablespoon per 5 gallons is around 0.1%
A LOW concentration is up to 0.1%.  This concentration will not hurt most plants and is what is typically used in ponds and tanks. Addition to fresh water is done over 3 days.

A MEDIUM concentration is up to 0.5% .  Addition from 0.1% up to 0.5%  should be done over a couple of days.

HIGH concentrations are up to 0.9% which is isotonic or the concentration within the fish.  This concentration is used for medical reasons for very short baths. THIS CONCENTRATION CAN BE DEADLY TO FISH.

mild nitrite protection = 0.1% (3/4 teaspoon per US gallon)
preventive and nitrite protection =  0.3 %  (2 1/2  teaspoons/gallon)

What kind of salt
Noga recommends "solar" salt WITHOUT ANTI-CAKING additives.  The additive is sodium ferrocyanide (yellow prussiate of soda) which makes hydrogen cyanide when exposed to fish.  On the topic of salt, p. 295 talks about salt dips for treatment of ecoparasites, columnaris and bacterial gill disease, and how salt dips remove the excess mucus making medications more effective against pathogens.  Solar salt can be bought in food stores, in crystal form, no additives for water softening in big bags for cheap.  Rock salt dissolves slowly.  This means it will not flash burn the gills or skin like adding finely crushed table salt will.  Almost all GF books specifically say no iodine.

Dips are brief exposures of a fish to a medication followed by the fish being put into fresh water.
flashing or flicking
coming out of the summer pond and into an aquarium
the fish just arrived in a box or just brought home from the store
the fish isn't looking "well" or hasn't responded to topical treatments for
"fin rot or dots"
under a microscope, parasites are seen in substantial numbers
the fish has a resistant case of fin rot

The fish are very small or fry ****** see caution
The fish have never been in "salted water" (like Israeli koi or shubunkins)
The fish is very toxed out from ammonia or other toxins (gills are dark red
or bloody looking)

1/2 cup salt with no additives per gallon of tank water (no temp shock)

0. mix the salt into the water.
1. put the fish into the salt water and start timing the dip.  A salt dip of 30 seconds for small or stressed fish is sufficient.  Fish can be dipped up to 5 minute if they continue to swim without sign of distress.
2. the fish will come up to the top, generally on its side, poke the fish and the fish will dive and swim
3. if the fish doesn't dive or doesn't dive quickly, take the fish out and put them into fresh water.  It is not a good idea to put the fish back into the tank they came from until that tank is cleaned out or treated first for parasites.
4. take even a still active fish out after 5 minutes, leaving them in the salt dip longer will kill them.
5. for SMALL FISH, when they come up to the top and start rolling even slightly, they must be removed immediately no matter what the time limit. This means their gills can't handle it. Even if it has only been a few seconds.

1. the fish may dive to the bottom of the tank and sit there, this is usual
2. after the dip, the fish will "purge" both feces and ammonia from the gills, so the water must be tested and the water changed

DYLOX or trichlorphon must be used every 7 days for 28 days. Trichlorphon is a very toxic and harsh medication and resistance is common.  It is cumulative, affects the nervous system and can be absorbed through the skin.  Hands should be kept out of the water while this product is being used.  It can cause spinal deformities if fish are overdosed.
Noga suggests Diflubenzuron as it is less toxic to fish, not inactivated by high temperatures and highly effective.

Copper sulfate is toxic to fish in acid water, and if hardness is less than 50 or greater than 300 ppm.  Copper kills invertebrates.

    The primary cause is feeding food that floats and/or too much food at one time.  Soak the food and squeeze the air out so the food sinks.  It is better to feed twice a day for 3 minutes.   If feeding is only done once a day, feed at night, and all they can eat for 5 minutes.
    The other parameter here is temperature.  Increasing the temp of the water seems to ease the floating problem.  The activity of their digestive tract increases with increased temperature.  However, increased oxygenation of the water must be done at the same time.  Temperature can be safely increased to 84- 86oF with good aeration.
    For a fish that is already floating, check the belly.  If the fish is fine according to the 3 point check, or if the fish is constipated:
    Start with feeding sinking food if the floating is after eating.
    Next is to skip a meal and see if the fish stops floating, then resume feeding but soaked/sinking food with  a green veggie  like peas at every meal.
    The more aggressive approach is to feed a pea with a crystal of epsom salts (magnesium sulfate) in it to the fish.  Epsom salts is a purgative.
    Even more aggressive is to do a salt dip on the fish. This purges the fish out.  Ammonia levels must be watched carefully.
    If this doesn't work, there is a procedure called the "Chinese Water" method.  I have not had any luck with it, but The Goldfish Guru swears it works for her.
    The fish is put into a tub and only enough water is added to just cover the back fin.  The fish is not fed for 4 days.  If the fish is upright, each day a little more water is added (the fish must be moved to fresh, aged water each day to move it away from ammonia accumulation). After 4 days, if the fish is upright in deeper water, then a couple peas can be fed.  After that, gradually add a little more food.  Small fish cannot be not fed for that long.

    Changing the water is undoubtedly the most important and risk free treatment for fish.  The tank water should be tested first for toxins (it helps to know if the nitrites spiked), then change the water immediately.  If the fish start acting better in an hour or two, that may be all the treatment that is necessary.  When using medications, changing the water is essential for two reasons.  It dilutes medications out before the new dose is added, or after the last dosage to get rid of the meds (usually no more than 3 days).
    Water changes gets rid of free swimming parasites or bacteria. In fact, the tub to tub method of treatment is superior for this reason.
    WATER MUST BE THE SAME TEMPERATURE (within 4oF) or it will shock and possibly kill the fish.  It must be nearly the same pH for the same reason.  From 25-100% of the water can be changed.
    CAUTION: If you won't drink the water because it tastes bad, or your fish are not happy after water changes, your water may contain trace toxins.  You can order the chemical analysis from your water department and also find out what additives they are using.

The Chinese found early in the history of keeping Goldfish that moving fish to fresh water every day could overcome disease.   In the past 5 gallon buckets were suggested, but my experience is that the GREATER THE VOLUME OF WATER THE BETTER.  I generally use a couple of extra 20 gallon tanks I have sitting around, but a couple of  20- 40 gallon rubbermaid tubs serves the same purpose.  When not in use they stack and can be filled with all that  miscellaneous goldfish stuff that accumulates.

1. Rinse both, fill with fresh water, add dechlor if needed and put an airstone in both.  A single double outlet wave castle air pump from Kmart will do for both.  Put the sick fish in the first tub while letting the water age overnight in the other.  If the water is to be heated (for dropsy) add the heater.  If heat is needed, then either two heaters are needed, or some of the water in the second tub can be heated and mixed until the correct temp is reached right before the fish is moved over.
When using medications, aging the water will get rid of the dechlor which inactivates the most commonly used medications.

2. Put the fish in the first tub with an airstone. Add the medication (if any).  With a larger volume of water it is unlikely that the ammonia level will climb very high, but check the ammonia levels after 12 hours.  If the ammonia is more than barely perceptible,  move the fish to the tub of aged water without waiting.  Otherwise, wait 24 hours, then move the fish to the new/aged tub of water.  After moving the fish, dump the water out, clean it well (I use the soap-less betadine on an aquarium sponge), put in water conditioner and let it age overnight.

3. Feed fish in the tub about an hour before you move the fish.  They will eliminate soon after eating.  Then move the fish.  This leaves behind the excess food and wastes and keeps the water cleaner.  If dips are being done add the meds to the water, leave the fish in for the prescribed time then move the fish to the new water.  If meds are going into the water for continuos use, then add to the new aged water and mix well before moving the fish into the new tub.  Most meds will spot burn a fish if too concentrated.

   Fresh water in a tub overcomes several problems.  First, there can be something toxic in the tank, gravel, stones, decorations, wood, sometimes there is nothing that can be identified.  If only one fish is sick and the others are fine, getting the sick fish out to recover is essential for keeping the other fish healthy.  A sick fish sheds disease into the tank and makes the tank unhealthy.  Moving the fish tub to tub moves the sick fish away from parasites or bacteria they are shedding and this helps them recover.

     Because there is no filter (unlike a quarantine tank generally used for a month), there is less likely to be something in the filter that is the problem.  20 gallon glass tanks have one benefit, the whole fish can easily be seen.  2 - 20 gallon tanks sit on the typical stand for 20 gallon tanks and do not take up much space.  But if there just isnt room, the tubs are the next best alternative.  Tubs are also great backup in case of cracked tanks, an unplanned purchase of fish, or in case of eggs/fry suddenly showing up.

When you feel that the fish is suffering, the way to put them to sleep is to put them into a zip-lock sandwich bag with some tank water and a little salt and put them in the freezer.  The fish goes dormant and then slips away as it freezes solid.  Most of us with ponds that freeze over sooner or later find one of our fish frozen in the ice.
There is another way, and that is using clove oil which is also used as an anesthetic (for shorter time!).  "It depends on the size of the fish for the number of clove oil drops, but for under 2" fish, 10 or so drops does the job well.  Put the fish in a small container (I've used drinking glasses for this) of tank water and drop the oil in.  Let the container and fish stand at room temp for 10-15 minutes, or until euthanized.  The larger the fish, the more drops would be required " Add 1cc Clove oil (eugenol)  to 3cc of Vodka, mix and add this to a gallon of water. Put the fish in until they aren't breathing anymore, then put in freezer bag in the freezer just to make absolutely sure.