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SYMPTOMS: gasping, darting, hyperactivity. Cloudy, thick slime coat
 check pH; ammonia, nitrites; gills; slime coat
TREATMENT: slowly bring pH up with water changes, aerate well
SOLUTION: clean gravel/get rid of organics, increase buffering capacity of water,
                   increase aeration

When the pH drops below pH 5.5, acidosis occurs.  At low pH the fish begin darting around the tank, breathing rapidly, and/or may jump at any movement near the tank.  Death can occur very quickly if the drop is rapid (pH shock) even when the pH does not reach 5.5.  When the pH drops slowly, the same symptoms will gradually emerge; gasping due to lowered oxygen carrying capacity of the blood, heavy slime production which reduces oxygen exchange over the gills, the precipitation of any metals in the water into the gills, fish darting into the side of the tank.  Metals are very toxic at low pH.  Gills will be dark red to almost brownish.

Pond fish are more tolerant of pH fluctuations than tank fish.  Outdoors, submerged plants/algae make carbon dioxide during the night. CO2 dissolves in water and makes an acid that can drive the pH down into the 6.5 range.  In the morning the plants/algae use the CO2 and the pH rises.  At night, algae filled or polluted ponds/lakes can also use up the dissolved oxygen.  This means the fish are either gasping at the surface or found dead in the morning. The largest fish die first.  Immediately increase/add aeration whenever a fish is seen gasping at the surface. This is one reason that pumps and waterfalls are never turned off, especially not at night.

Dissolved CO2 cannot drop the pH to 5.5.  But decaying organic matter in the tank or pond will drop the pH that far.  Feces and rotting food in gravel in the bottom of tanks, dead leaves etc. in the bottom of ponds decay without oxygen.  This leads to incomplete breakdown and the accumulation of organic acids, fermentation products, including toxic gases.

The other consideration is that the two primary nitrification/cycle bacteria, Nitrosomonas and Nitrobacter are sensitive to pH.  Low pH kills the biofilter.  Nitrobacter dies first, and the nitrites rise forming nitric acid.  This kills the Nitrosomonas and the ammonia rises.  Nitrite poisoning turns the gills of the fish almost brown.  If the ammonia and/or nitrites are high, it is better to adjust the pH of fresh water to the existing water and move the fish to fresh water to prevent further damage from the toxins.

If the fish survive, they are going to be very stressed.  Stressed fish have a poor immune system which leaves them susceptible to infection.  This is a case of "fried gills".  If the biofilter has been killed, they will need frequent small water changes to keep the water pristine.  They are going to need substantial aeration. Treating with medications must be resisted.  Fish with fried gills cannot handle medications except in foods, so medicated foods can be fed to prevent infections.  If the biofilter was killed, fish may have been burned so the appearance of black marks should not be cause for alarm.  This is a sign of healing.

Initial treatment:  Fish should be moved to a bucket of the tank water and the pH gradually brought up or the fish will suffer pH shock.  An air stone must be put in the bucket with the fish.  Make sure the temperature of the new water is matched to the tank water.  If the ammonia/nitrites are high, move the fish to temperature and pH matched fresh water immediately.

Solution: Clean the tank out completely and refill. (Especially if the biofilter is dead, consider switching to alternate types of biofilters and removing the gravel permanently). Increase the gravel siphoning frequency and thoroughness.  Or consider gravel on only 1/2 of the tank so food can be fed over the bare bottom part of the tank. Determine the hardness of the water.  It should be at least 50 ppm of total hardness or get organic dolomitic lime (best) or crushed coral to provide a buffer system.  Baking soda is a carbonate and a good buffer, but it gradually leaves the system and is not a long term solution.

In a pond, the fish must be removed and the bottom of the pond cleaned.  A sewage pump works well for a heavy build up of rotting leaves.  If the water is naturally soft, organic dolomitic lime or crushed limestone will add buffering capacity.  Do not use slaked lime as this can cause a rapid pH change that can shock fish.  Increasing aeration with foot long air stones and an air pump will turn the water over bringing oxygenated water to the bottom of the pond.  This (combined with a good mechanical filter) will allow aerobic breakdown of organics and prevent the buildup of toxic products on the bottom.

SYMPTOM: darting, gasping, red streaks, sudden death
check pH;gills; ammonia
TREATMENT: bring pH down slowly, aerate well
SOLUTION: cycled biofilter, seal concrete

When the pH rises above 8.8 or so, Goldfish may develop symptoms similar to acidosis and/or ammonia toxicity.  However, GF like more alkaline conditions and are very tolerant of higher pHs.  The problem is that ammonia is much more toxic at high than low pH.  Alkalosis is most often a problem of cycling filters.  If due to high ammonia levels, changing the water frequently until the filter is cycled is all that is needed.  If gills are dark red, do not use medications.

Alkalosis can also occur when new concrete ponds have not been acid treated or sealed.  High levels of lime leach into the water, rapidly killing the fish.  Any fish still alive must be moved out of the pond into water that is 0.5 pH units lower than the pH in the pond and the water gradually replaced down to normal tap pH.  The concrete must be treated to stop the leaching.  Limestone pavers will not rapidly leach lime unless the tap water is very acid.

Without warning, city water departments add various chemicals to the water that can cause a lot of problems.  They sometimes use NaOH, a powerful alkali. This can make the pH of the water jump quite high.  One reason aged water is recommended is that it allows time to check the water for pH, chlorine, etc. before putting it in the tanks.

SYMPTOMS: clamped fins, gasping, lethargy, hiding, thick slime coat
rule out pH problems; slime coat; gills
TREATMENT: 3% salt dip, then Quick Cure for 3 days
SOLUTION: better tank and water conditions, salt dip and treat fish when bringing them in from outside
This is a cooler water disease. This means that it can be a problem for fish that over winter outside.  Treat with Quick Cure for three day with 30% water changes each day.  In the pond, increase the salt to therapeutic levels.

SYMPTOMS: lethargy, flashing, dry patchy looking skin, yellowish tinge, thick slime coat
 check for heavy slime coat, use a flashlight, do a scrape
TREATMENT: water changes, salt dip,Quick Cure for 3 days.
SOLUTION: improve water conditions, quarantine new fish
Oodinium is a disease (AKA Velvet) caused by a parasite. Infestation causes a velvety texture all over the fish or just in small patches.  The best way to spot it is to take a flash light at night and look in the area near the dorsal fin.  You should see very pronounced areas of dry patchy looking skin and this should have a yellowish tint to it.

SYMPTOMS: white threads blowing in and out of mouth, dry skin, skin color darkens, white  fungusy or thready looking sores, peduncle disease, red anal vent, chronic bubble eating
check for mouth and anal vent for sores; slime coat; mushy belly; gills light to dark brown patches, white sores
TREATMENT: potassium permanganate in the water, feed romet B, injection of antibiotic if possible. Topical treatment of wounds.
SOLUTION: improve water conditions, quarantine new fish.  It almost always indicates that a parasitic infection is going on and an accumulation of organic debris, including fecal matter.

There are two main kinds of infection, internal and external.  Some fish are carriers, others acquire internal infections when they eat fecal matter of other columnaris infected fish.  Internal infections may cause adhesions of internal organs.  In fancy GF, this can damage or bind the swim bladder to the point that floating problems occur.  This may be one reason some fish are chronic air bubble eaters and are unsteady in the water.

In most cases, the only symptom of an internal infection is redness in the mouth or at the anal port or some thready material around the mouth.

The problem with columnaris is that when it is inside the mouth and the scales are lifting with no signs of an outbreak it usually means it has gone systemic.  You cannot treat the nodule if it hasn't ruptured yet, so the only alternative is medicated foods.  When there is an external infection, the wounds seem to appear over night.  Jo Ann


TREATMENT: bring fish to surface, as it opens its mouth, use long, rounded tipped tweezers to grasp and pull out the stone.
SOLUTION: either remove the gravel completely or use gravel too large to fit in the largest mouth.

Usually you can kind of turn the rock around and loosen it and then you can grab it with the tweezers and pull. It should take no more than 30 seconds or so, but no more than 2 minutes or put the fish back in the water and try again in a few minutes.  As you raise him out of the water he will slightly open his mouth or just take the tip of the tweezers and gently force the mouth open until you can see with the light. Try to hold him as gently as you can and make sure your hands are wet.  If at first you don't think you can do it remember if he does have a rock you are the only link to saving him!!! Jo Ann

SYMPTOMS: pitting, depigmentation along the lateral line near the head, thin white threads trailing

TREATMENT: change feeding, carbon,
SOLUTION: better nutrition

Tropical fish like oscars and angels seem to be very susceptible to Hole-in-the-head disease.  In Noga, they apparently think it is due to Hexamita, a parasite followed by bacterial infection. Starts as pitting and depigmentation in the head area, usually along the lateral line.  Later pinpoint lesions are seen with thin white threads of stuff coming out. Think it is due to mineral imbalance and/or declining immune system in stressed and/or older fish.  Alternate theory is mineral imbalance which makes lateral line pits enlarge letting bacteria get in.  One other theory is some carbon filter material predisposes fish, mechanism unknown. They suggest better nutrition (provide calcium/phosphorus/vitamin D supplement), less crowding, more water changes. Change or don't use filter carbon.  Can treat Hexamita with METRONIDAZOL (food made by Tetra).  Feed antibiotic food.

SYMPTOMS: mottled gills, bluish or grayish irregular streaks
hot temps and bluish color are the tip-offs
TREATMENT: salt dips, scrape the fungus off, move to fresh water everyday, or open raceways
SOLUTION: improve water quality

It looks like spring viremia, or bacterial disease.  But if the gills are mottled, or bluish gray streaks are showing up, it is Branchiomycosis which is a fungus.  This disease gets hold in conditions of high organics, possibly high ammonia, hot temps.  It infects the gills first, they will appear mottled.  It spreads from the gills.  It is very, very difficult to treat.

The Goldfish Guru suggests: 3% salt dips. Move them into fresh water.  Then try to physically remove the grayish crud.  It should dislodge pretty easily.  Don't be alarmed if the skin comes with it, leaving an open wound.  The skin is already infected.  Apply neosporin CREAM to the area, rubbing it in really well.  Panalog, available from a vet, is much better. Salt dips can be repeated if all the crud doesn't come off.  The fish need antibiotic food, to prevent bacterial secondary infection. The best is romet-B.

Most Koi are raised in "raceways", that is in continuously flowing water. When these fish are put into a pond, they don't cant cope with low oxygen levels, with high organics.  Hot temps and algae blooms makes the oxygen problem more severe and they are so stressed their immune system crashes.

Israeli koi are worse, they are raised in nearly sterile conditions and have little to no natural immunity to most diseases.  They are also not raised in "salted" water, so putting salt into the water is toxic for them.

The best treatment for this disease is to put fish into a tank with a continuous drip of water.  This will cool them down for a start, but it also is optimal for the fish to recover.  SINCE THE FISH ARE ISRAELI, salt in the water cannot be used.

If anyone has a microscope,  the fungi look like snow flakes instead of the typical long hyphae.

SYMPTOMS: white specks like grains of salt all over most of the fish
check if temperature of water has change suddenly, check water parameters
TREATMENT: Quick Cure for 3 days
SOLUTION: make sure the temperature of the water when doing water changes is constant, improve water conditions, feed antibiotic food in fall when temperatures start to decline in the pond, use a tank heater to prevent temperature drops when air conditioners are used, or when tank temperatures fluctuate more than 2-3 degrees per day.

According to Noga, p. 95, the ich of freshwater fish does not lay eggs, it has a complex life cycle.   What we see as "grains of salt" is the feeding stage in a nodule under the skin. This stage is resistant to medications.  When it has fed enough, it breaks out, falls off and forms a capsule that doesn't do anything but make up to 10 little ich mommies (this is what is easily seen in a microscope at very low power (40X) and the darker nucleus looks like a horseshoe or a big "C" in a very big cell).  They break out and reproduce like crazy, each one making over 1000 infectious progeny.  The whole cycle is very temperature dependent.
    77oF -- 3-6 days
    50oF -- a month or more
In heavy infestations, the individual "salt grains" may form into mucoid (thick slimy) masses on the skin.  Fish with these generally don't survive even if treated. The feeding stage itself causes erosion and wounds which can quickly be infected by bacteria, etc.  When a fish recovers from infection, they acquire some immunity to another infestation.

Formalin: 0.09ml per gallon. 3 treatments on alternate days. At 24-26oC, the ich cycle is done in 7 days.
Formalin and malachite green (AKA Quick Cure) every other day for 3 treatments with 50% water changes on the off day
I use a 3.0% salt dip and QC for 3 days in a row with 30% water changes every day and it has been effective, but I did get the temp up to 72-74oF.

CAUTIONS; the capsule stage is sticky and nets and aerators must be disinfected or it will spread it to other tanks or back to the original.  Birds, etc. that go from pond to pond will also move the capsules.

 for pictures

Dropsy is a SYMPTOM of other problem(s) with the fish.  Dropsy can be due to problems with the environment (water quality, temperature shock, alkalinity), parasites, bacteria or virus.
The symptoms are:
1. scales lifting (pine coning) and/or
2. swelling without scales lifting (ascites) and/or
3. both eyes bulging (exothalmia)
Many people say that dropsy isnt curable. The earlier that dropsy is caught treated, the better the prognosis. Here are pictures of a VERY dropsied fish before and after using Jo Ann Burke's treatment method for a fish with dropsy caused by bacteria.  Click HERE or on the name DROPSY.

Are both eyes bulging?  Fish with only a single bulging eye is most likely mechanical damage. The best treatment for this is clean water and a little salt.

Check the water parameters, ammonia, nitrites, nitrates, pH, alkalinity and temperature.  Was there an ammonia or nitrite spike?  Are nitrates high?  Was the temperature of the water matched during the last water change? Was the alkalinity of the water changed suddenly?

Do Jo Ann's 3 point physical.  Are there any indications of fried gills, bacterial infection, parasites?  Have the fish been showing any other behaviors of degraded water quality, parasites or bacteria?

Do a scrape and look for parasites if you have a microscope.

If the temperature in the tank or pond has dropped suddenly, prognosis is very good for treatment.

TREATMENT:  If parasites are likely, treat for them first for 3 days increasing the temperature to 86oF as fast as possible.  Do NOT use salt, use epsom salts and use extremely good aeration.
SOLUTION: Check the temperature of the water when doing water changes.
Water quality must be maintained.
Feed antibiotic food in fall when temperatures start to decline in the pond.
Use a tank heater to prevent temperature drops when air conditioners are used, or when tank temperatures fluctuate more than 2-3 degrees per day.

Pop-eye is sometimes caused by Edwardsiella ichtalori (info supplied by the Goldfish Guru).  It is carried by frogs and turtles, especially if you are in the south.  Feed Romet B, but better is
inject chloramphenicol if in the south or amakacin if in the north (amakacin seems to be pH dependent, works best in alkaline water).

A number of us have found that  keeping the heat up to 84-86oF of for 2 weeks minimum, keeping oxygen levels high and feeding with antibiotic food like Romet B has brought most of them around.  We don't know for how long.

Little to no salt, and 1/8 teaspoon of epsom salts per 5 gallon water.  The temp alone kills most strains of Aeromonas.  Feeding erythromycin laced food (soak dry food) or romet B will kill the second suspected bacteria, mycobacterium.

The salt thing is counterintuitive.  It is rational to think the salts would "draw" the fluid out, but actually, the fish is having a hard time getting rid of salts, which is why it is blowing up.

The epsom salts, on the other hand,  will not pass through the walls of the gut or gills, and is supposed  to "draw out toxins".  It definitely pulls water out of the surrounding tissue into the gut when used as a laxative.

  No one is sure if this is a cure (when done for at least 2 weeks).  But I have not had a relapse so far (7 months I think) if the fish make it through dropsy.

Dropsy and ascites are different.  In both cases fish blows up, but when the scales stand out, this is more normally called dropsy or pineconing.  This is more treatable.  Ascites, when the fish blows up but the scales are flat usually goes along with no ammonia which points to kidney damage.  If the fish has ascites and is producing ammonia, maybe this too is curable.

In discussion with Jo Ann, of the 5 causes of dropsy (parasitic, bacterial, viral, temperature shock, toxic water), Jo Ann says caused by bacteria can be cured by high heat because aeromonas is killed by high heat.

I am not so sure that heat is only responsible for killing bacteria.  Bob Gray talked about dropsied fish that were only fine in hot water, the minute the temp was reduced, they dropsied again.  It didnt seem that the bacteria returned, rather it seems to point to some physiological defect where the fish could not regulate water intake/output at lower temps.  In humans, some people get heat stroke and once they have had it once, they are always susceptible.  It is tied in with electrolyte imbalance as ingesting gatorade AND taking cold showers reverses the condition.  Without taking electrolytes and bringing the temp down, the body temp just keeps rising until coma and death.  So electrolyte regulation is tied in to heat somehow.  And electrolyte imbalance is tied into edema, like in congestive heart failure, where fluid is lost into the tissues across the capillary bed and cannot be brought back in.

GF whole metabolism is tied into temperature.  Dropsy is the loss of electrolyte/fluid control.   In GF, it seems the imbalance and swelling works opposite of humans.  A quick drop in temp can trigger dropsy.  And moving fish from soft to hard water can cause dropsy.  So I think that bringing the temp up may treat dropsy by another mechanism, as in the case of Bob's fish.

Reason why the heat method doesnt work for some fish
Bacteria are rarely the primary infecting agent.  Fish are normally quite well protected  against bacteria by their slime coat.  Parasites large enough to get thru the slime coat disrupt the slime coat and allow bacteria to enter.  If GF with active parasites are moved into hot water, this  causes an explosion of parasites (who's reproduction is tied to temp).  So the parasites have to be treated first.  If the fish isnt badly dropsied, a quickly salt dip and a day or two treatment at lower temps with medication is called for.  If the fish is badly dropsied, there may be no time for medication, then a quickly salt dip (30 seconds) that kills some of the parasites outright, and reduces the number of them by stripping the slime coat must be used.  The fish must be put into fresh water to prevent reinfestation from without.  Moving them to fresh heated water every day keeps them from reinfestation.  Again, running the temp up with an active parasite load can kill the fish.

Reason why the heat method doesnt work for some fish
NaCl salt has to be removed from the system and magnesium epsom salts added, but only 1/8 teaspoon per 5 gallons.  More is not necessarily better.  Softened water may contain quite a bit of sodium ions without being obvious by taste.

Reason why the heat method doesnt work for some fish
Fish are moved to hospital tank to protect tank mates, but also in case the dropsy is due to poor water conditions in that tank.   When fish doesnt respond to fresh hot water, this does not rule out toxic water as there may be some basic underlying problem with the water, not enough natural electrolytes, alkalinity, carbonate hardness/buffer or something, right out of the tap.  When fish do respond, it is time to investigate what may be toxic in the tank they came from,  like carbon leaching crud back into the system, or gravel  leaching dyes or organic crud or toxic gases.

Reason why the heat method doesnt work for some fish
The temp is run up fast, not slowly.  It is rapid temp DROPS that can shock the fish.  Running the temp up is not the same as taking a fish from cold water and dropping them into hot water.  Bacteria replicate in as little as 20 minutes, and adapt incredibly fast to "marginal" conditions by natural selection.  Inching the temp up slowly may select for those bacteria that can function/reproduce at higher temps.  I dont know that this will in fact happen, but using marginal conditions for selecting resistance is done all the time in the lab.

Reason why the heat method doesnt work for some fish
No treatment, not even antibiotics kill every single last bacteria.  The fish MUST have a functional immune system to regain health by developing immunity that does stop bacteria and viruses.  If the fish is so stressed by conditions or toxic water, or by the addition of medications,  they will not have functional immune system.  All medications are toxic to one degree or another.  Medications that are USELESS not only do nothing to help the fish, it may prevent the fish from recovering.  Jo Ann has basically tested most of them on the market.  She has found the meds that work, the ones that dont and the ones that are simply too toxic to be useful.  Now, she hasnt tested them all, and, Jo Ann points out that meds toxicity and usefulness IS different in different kinds of water, soft vs hard for example.  IN GENERAL, antibiotics in the water dont work.  Injected is best,  followed by antibiotic food.  As an addition, the immune system "turns over" very fast.

Reason why the heat method doesnt work for some fish
To build immunity fish need protein and energy.  They need GOOD food with antibiotics in it.  Fasting them is not helpful.  As long as fish are pooping, they should be force fed if they are not eating.  A fish has enough reserves for a couple to 3 days, after that, get out the syringe.  If the fish wont eat the romet B but eat a little chopped shrimp can be fooled by soaking romet in shrimp oil or other fish oil.

Reason why the heat method doesnt work for some fish
 Get a good thermometer.  With aeration, the temp can be set to 86oF to make sure the water stays warm.  New fresh water must be kept above the minimum of 84oF.  It takes a minimum of 4 days for dropsy to begin to resolve, to see the scales starting to return to normal.  And it takes a month for "the treatment to "hold" in most fish when the temp is finally lowered.  The fish doesnt have to be moved bucket to bucket for the whole month.  The bucket to bucket method keeps the fish ahead of anything they might be shedding and preventing reinfestation.  A few days after the scales are down, the fish can be moved into a tank with a filter (make sure the filter is clean) as long as the heat is continued.  When the treatment is done, it needs to be lowered slowly, like 2oF per day until it is at the temp the tank of the other fish are kept at.

Reason why the heat method doesnt work for some fish

First you need to treat the parasites if the fish is out of a pond.  If the slime coat is still thick, a quick salt dip will strip it off, then PP or Quick Cure for 3 days.  Do this in a bucket, moving the fish to fresh water every day or more depending on ammonia buildup.  You have to heat the water up to 84-86oF and add 1/8 teaspoon per 5 gallons.  An injection of antibiotics is good, but if no access, feed romet B antibiotic food or soak something dry in oxolinic acid.  It takes a minimum of 2 weeks (and more like 1 month of moving the fish every day and heat to stop the dropsy.

Don't quit the heat if the scales go down.  Don't stop the epsom.  It takes this long to get the toxins or whatever out of their system.  Stop sooner, and they relapse easily.  Dropsy can also be caused by quick drops in temps, but only in susceptible fish.

Fish Louse. (Argulus) are flattened with a roughly round body with eight legs and two large hooks (not usually seen) to attach to the fish.  It is about 1/8th of an inch and the dark eye spots give it away.  It sucks blood, so removal involves making/leaving a wound which needs to be treated with a topical antibiotic.  Eggs are attached to things in the tank and pond and they hatch out about a month later.  They are suspected of spreading other diseases.
Remove with tweezers.  Treat site with neosporin or Panalog creme.  In a pond, the best treatment is Dimilin (3 times 6 days apart, 0.01 mg/L).  It has a wider range of tolerance than Trichlorfon that needs to be used every 5 days for a month.  Dylox is a trade name.

Only females attach into the muscle of the fish and feed.  The long body and forked tail is diagnostic, a microscope is not needed.  .
Remove with tweezers.  Treat site with neosporin or Panalog creme.  In a pond, the best treatment is Dimilin (3 times 6 days apart, 0.01 mg/L).  It has a wider range of tolerance than Trichlorfon that needs to be used every 5 days for a month.  Dylox is a trade name.

If the infestation is not on a single, newly acquired fish, but has spread to all the fish in the tank,  rubbermaid buckets or containers are needed.  Put water in them, treat, age overnight with an airstone (you will need two airstones).  One by one, pick up, exam and remove the lice or anchor worms, putting the cleaned fish in one of the "buckets".  Take everything including the filters out of the tank, clean and let them dry out completely for a couple of days.  The eggs will stick to everything. Toss plants.

You are going to have to recycle your tank with new filter material.  Be sure that the bucket of water has good aeration, use the biggest stone possible.

The next day,  check the fish again for lice, salt dip the fish and move them to the next bucket of water.  Clean the first bucket with bleach, also the airstone, add dechlor and water and age overnight.

Repeat this checking and moving the fish (without the salt dip) for 10 days.  You are moving the fish away from any eggs that might be in or on them.  Be sure to clean the bucket and airstone each day and move the fish.

Put the fish back into the tank and start cycling again, changing a lot of water to keep ammonia down to barely detectable.  Both pierce the fish and suck, in doing so, they introduce other parasites and bacteria.  A little salt in the water helps stimulate the slime coat which contains antibody.  Hopefully, they will shed slime coat that could contain the eggs during the 10 days.

SYMPTOMS: black spots

TREATMENT: salt dips, salt in the water and water changes
SOLUTION: get rid of snails

According to Noga, if the fish has "black spot disease" there is no OTC treatment for the metacercaria (which are not in themselves lethal).  They will simply "come out" of the cysts.
If there are no snails or copepods around, that is the end of the line.  However, while the metacercaria are there, they can cause an immune reaction, which can be hard on the fish.  If/when the metacercaria come out, they leave behind a hole that can get infected with bacteria and/or bleed.  That is a danger to the fish.  Salt in the water helps healing and increases production of the slime coat.  Frequent water changes dilute out any possible infectious bacteria and supports the immune system.  The key for fish survival (if they do not bleed to death from the holes) is a good immune system.

In ponds, copper sulfate can be used to kill off the snails.  That stops the infection from spreading to other fish.  Before using copper, however, make sure your water hardness is greater than 50 ppm and less than 350 ppm and pH is close to 7.0.  Acid water and high or low hardness renders copper very toxic.  Dimilin (hard to get, expensive)  will kill snails and is not toxic to fish over a wide concentration.

Using water changes and salt (rock salt) for 48 hours will let you determine if the spots are due to burns.  If you absolutely, positively must put something into the tank, 48 hours is not going to make a difference for "black spot disease".

Black Spot is due to the metacercarian stage of a parasite with a complex life cycle called a "digenean" trematode .  The "black spot"   is caused by the metacercaria encysted under the skin which irritates the melanocytes of the fish tissue, causing the dark spot.

As long as it is under the skin, it is impervious from outside.. don't know about feeding anti parasitic.
But fish don't normally die. Generally, water conditions have to be pretty poor for this to be deadly.  It is passed by snails, in fact, snails are essential to its life cycle.

Myxosporidiosis is a generic term for protozoan infections like Henneguya (looks like happy face in a microscope).  It is one of several protozoans that attack the gills.  In good water with good aeration, it does not cause high mortality.  It looks like a white cyst in the gills.

The only treatment is supplemental aeration (according to Stoskopf) and using a "flushing" system.  According to the Goldfish Guru, formaldehyde is put into a vat in higher concentrations.  Then water is dripped in constantly to flush the medication out and with it the dead or dying bugs.  This way as they
hatch out,  they cant re-infect.  Symptoms of myxos is fish at the surface acting like they cant get enough air.  Gills are pale.  In later stages some protozoans cause the gills to look like raw hamburger.  This is from when they rupture and exit the cysts.

Costia is a parasite that nearly always causes little red hemorrhages, especially under the chin, but also along the back.  If the red dots are under the scales, it is more likely to be bacterial.
Costia can be seen at 100X and identified by their very fast altho jerky movement.  They are oval with a dent, making them sorta kidney shaped and have two pairs of flagella which arent always easy to see except at higher magnification.   Costia can divide every 10 hours at 75-78oF, but die at 86oF.  They can divide at low temps, so is already causing a problem in the cold spring problem.
TREATMENT Salt dip to strip the slime coat, treat for 3 days with Quick Cure and then run the temp up to 86oF for 3 days.  Slowly lower the temp to normal, 4oF per day.

Aeromonas is AKA "spring crud" in the catfish industry as it gets going quite early in spring.  A vaccine is great, but it has to be done in fall when the temps are high enough for the fish's immune
system to be up and running or the vaccine wont "take".  Aeromonas can infect fish all by itself, but a parasite infestation will bring it on faster.  The catfish farmers (from what I have been told) say that feeding Romet B in fall will stop aeromonas in spring.  Romet B is fed to koi in spring after temperatures warm up.

Look for any red sore.  Evidently, any red sore is bacterial according to the latest evidence (conference in Florida).  If a fish in cold water (below 60oF) is found to have a red sore, they have to brought in and warmed up slowly (2o per hour).  Then salt dipped and shot up with Baytril.  0.1 ml per foot of fish, an extra 0.1 ml for "heavy" fish.  Inject once, wait a couple of days and inject again if the fish isn't responding.

The wound has to be cleaned with peroxide and Panalog rubbed in well.  Peroxide once, Panalog twice a day. Slowly, the temp must be raised to 84oF (tenting helps get the temp up). This temp kills aeromonas (all but the jendai strain, high temps activate this strain).   Baytril and panalog can be obtained from vets.

The injection site is just off the midline, 1/3 of the way from anal port to ventral fins.  Use TB syringe, shallow angle towards the head and under a scale, hold plunger down when removing the needle.  This injection site is good because you cannot inject easily if in the wrong place.   These instructions are for a vet if you haven't injected animals before.  TMP-4 or sulfa with trimetheprim (or Romet B) are best given in the food rather than in the water and is safer and preferable.  That way a fish can be treated externally for parasites and fed antibiotics.   Any fish brought in from a pond is almost certainly going to have parasites.

The temp cannot be raised for the bacterial problem without getting rid of the parasites since increased temps will stimulate the parasites.  A fish's immune system is not up and running for about a week after the temps increase.   After a salt dip, Quick Cure for a couple of days will knock almost everything down to a reasonable level (except anchor worms or argulus).  But add it at night as it is light inactivated.  Fish have to be kept in quiet and reasonably dark place when coming out of a pond.  And netting must be used as they will jump.  Also, aeration must be done with increased temps, biggest stones you can find.

Blood at the base of the pectoral fins may be the first indication of an internal infection.

Fish are typically thinner in spring after not being fed over winter.  If there is a high load of fish in the pond, there might not be enough natural food and the fish must be fed.
But the fish seem to be eating but look sucked in at the gill plates, the head looks large compared to the body and the body is "skinny" , this is most likely "skinny disease".  It was thought to be viral and fatal, but has recently been found to be due to a bacterial problem that is treatable with erythromycin in the food. 1.5 gm per pound of food for 10 days.

If it is greasy, buff colored and shiny, it is most likely carp pox.  Especially if the water is just warm ing up or is cooling down (in your area).  You could add some salt to the water, and see if it disappears in a week.  If it gets bigger or more of them and they are found on the edges of fins,  it could be EPISTYLIS.  Then treat with a formalin based product.  Several parasites in this group and viruses cause the epithelium to "overgrow" which makes it look like warts.
for pictures

As the water warms up, and the water quality degrades, epistylis can occur.  They are more likely to be found on fins especially the edges.  Treatment is cleaning up the water and Quick Cure for 3 days.

Fish shakes head to propell himself forward, rarely using the tail.
Tubifex and the Whirling Disease Connection
   1995. Upenskaya, A.V. Alternation of Actinosporean and Myxosporean phases in the life cycle of Zschokkella nova (Myxozoa). Journal of Eukaryotic Microbiology 42(6): 665-668.
Abstract: Experimental evidence has been gathered to show that the life cycle of the myxozoan gallbladder parasite Zschokkella nova Klokacewa, 1914, which infects the fish Carassius carassius, has a complex life cycle with alternation of two hosts (fish and Oligochaeta) and two developmental phases (myxosporean and actinosporean). The gut epithelium of the oligochaete, Tubifex tubifex, exposed experimentally to Z. nova, obtained from C. carassius, became infected with organisms resembling Actinosporea. The spore structure and cube-like network of the interconnected spores is reminiscent of Siedleckiella silesica Janiszewska, 1952, although the spores are very different in size and number of sporoplasm nuclei. The life cycle of Z. nova resembles that of the whirling disease agent Myxosoma cerebralis described by Wolf and Markiw, which also alternates between fish and oligochaete hosts.

According to Noga, they are caused by Digenean trematode infections (Digenean fluke infection, metacercarial infection, black spot, white grub, yellow grub).  There are around 1700 species that infect fish.  uncommon in cultured fish.  Most damage is when cercaria migrate from gut to form cysts.  They are more unsightly than harmfull when grubs are seen just under the surface of the skin. However, when they erupt, they can cause bleeding and the fish can die from blood loss if there are a lot of them erupting.  Also the exit hole can get infected. Treatment: keep infect birds or mammals away from ponds, disinfect and quarantine, kill off the moluscs (snails), treat with praziquantel bath.

are more of a problem in warmer water so it is important to not increase the temp of water to treat bacterial disease unless parasites have been ruled out (usually with a microscope).

SYMPTOMS: Flashing, listless, frayed fins, slime coat thick or rough.

TREATMENT: Jo Ann Burke (the GF Guru) has been doing experimentation with treating flukes.  She has found that a 1 in 10 dilution of hydrogen peroxide (1 part OTC peroxide from the drug store {brown bottle} and 9 parts water) knocks the shit out of both dacs and gyros when the fish are dipped for 10 seconds (NO MORE).

Once the fish are dipped, the fins and slime coat get very ratty looking.  The fish will look normal in about 3-4 days.

She did not find it kills off any of the other parasites like costia, trich, ich.  Jo Ann has only had to use it once to get rid of flukes, but the guy at the U of Florida working with her has tried it on pond fish and found it may take a couple treatments.
It doesnt seem to matter if salt dips are used or not.
Stos and Noga both mention peroxide for dips and other uses.  HOWEVER, if you use their concentrations for the time they suggest it will either rip up the gills of GF or kill them.  Jo Ann tried a progression of concentrations and times (and sacrificed fish) to find that this is the minimum amount and the quickest time that eradicates the gyro WITHOUT any negative side effects!!!!!

OLD: 3% salt dip to strip off the slime coat followed by potassium permanganate for 3 days (at night).  Salt dips and Quick Cure will usually work.
SOLUTION: It is worse in warmer water and when water conditions are poor.  Most of the time fish carry a few of these.  A little salt in the water that stimulates the slime coat protects agains parasites in general.  Gyros are live bearers, they can produce a young every 4 or 5 days and live 12-15 days.  They feed on epithelial cells and can often be found in large numbers on dead fish.

SYMPTOMS: 1st sign... dark red at base of pectoral fins.  Later symptom, gasping at the surface, gloppy gills, flared gills

TREATMENT: Jo Ann Burke (the GF Guru) has been doing experimentation with treating flukes.  She has found that a 1 in 10 dilution of hydrogen peroxide (1 part OTC peroxide from the drug store {brown bottle} and 9 parts water) knocks the shit out of both dacs and gyros when the fish are dipped for 10 seconds (NO MORE).

Once the fish are dipped, the fins and slime coat get very ratty looking.  The fish will look normal in about 3-4 days.

She did not find it kills off any of the other parasites like costia, trich, ich.  Jo Ann has only had to use it once to get rid of flukes, but the guy at the U of Florida working with her has tried it on pond fish and found it may take a couple treatments.
It doesnt seem to matter if salt dips are used or not.  Because dacs are egg layers it is ESSENTIAL to continue to check for eggs up to 6 weeks and look for another batch of dacs and retreat.
Stos and Noga both mention peroxide for dips and other uses.  HOWEVER, if you use their concentrations for the time they suggest it will either rip up the gills of GF or kill them.  Jo Ann tried a progression of concentrations and times (and sacrificed fish) to find that this is the minimum amount and the quickest time that eradicates the gyro WITHOUT any negative side effects.   This treatment works against drug resistant DACS!!!

OLD:  Salt dips followed by PP or Quick Cure used to cure this, but now they may have become resistant to these drugs.  It can still knock their levels down, but moving the fish bucket to bucket is best as they are egg layers.  Sterilize the stones and buckets.
SOLUTION: maintain better water conditions and otherwise support the health of the fish
Dacs are flukes, much like gyros, but they found more likely in/on the gills and gill covers where it feeds.  The damage to the gills causes the gasping and stimulates over production of slime in the gills leading to gloppy gills.  Unlike gyros, dacs lay eggs.  Hatching depends on temperature, cool/cold slows hatching down, at 68-70oF it takes around 4 days.   Dac larvae can only last about 4 days without attaching and feeding.
The four eye spots are diagnostic and they can be seen at low magnification.

SYMPTOMS: white fleck in eye, swimming oddly or in circles
SOLUTION: get rid of snails

It is mostly round with a ring of cilia all the way around.  It is seen at 100X in the microscope where it spins and whirls so the movement can be seen. It thrives on the slime coat, so that conditions that stimulate the slime coat, like toxic water actually increase the numbers.
Clean up the water conditions, salt dip to strip off the slime coat and treat with Quick Cure.