In this
article that I have included in my blog, it hits many good and true points that hobbyist should read and take note on.
Many think that salt is a good prophylactic and will keep parasites at bay via implosion
of the parasites in fresh water systems and exploding in saltwater systems. But
this is only true in a quick dip of salt solution only and in the long term the
parasites will just adjust to any salt solution you put them in eventually and
the Koi will be no better off for it. I have even heard those that should know
better like MD’s tell hobbyist that salt will implode parasites if you keep a
constant level of salt in your ponds…this is not true and has no scientific merit
backing it up! Please do not fall into this misconception that salt will
protect your Koi, in the long run it does more harm than good, and this has
been scientifically proven.
Undergraduate students from the University of Michigan have
conducted an assortment of scientific research on salinity tolerance of
Cyprinid. The experiments performed were to gather information involving
salinity tolerances and preferences. The metabolic rate of Cyprinid was
measured at 10-ppt sodium chloride levels (saltwater aquaria has a specific
gravities of 1.020-1.025, which is about 27.30-33.75ppt.) and their metabolic rate
in freshwater was to be their comparison. It was establish that at 18° C. (65°
F.); Cyprinid would need a hundred percent more oxygen per milligram of body
weight than it would in just plain freshwater. In many books and magazines, it
states, “The salt will also help relieve some of the metabolic stress on the
fish so its immune system can fight off bad bacteria.” This statement by the
studies conducted by the undergraduates is very misleading and inaccurate.
Metabolic rates of Cyprinidae do not decrease, but increase, as salt
concentrations elevate. After all what animal currently: Breathes heavier,
drinks water continuously, when it normally doesn’t drink water at all and
needs more oxygen to sustain itself when it is supposed to be “relaxed”?
If you’re
using salt to lessen Nitrites toxicity in your pond then you have a filtration
problem that must be rectified A.s.a.p.; not putting a Band-Aid on it by using
salt like so many hobbyist do. In this case the hobbyist must realize that
their filter is inadequate or they just have too many animals for the body of
water they are trying to keep them in.
If bacterial reasons are why you are
using salt then you are definitely under the same misconception that salt will
lessen the number of cells that are harmful to our animals. Bacteria are very resilient
and will adapt to their environment and become super-bugs. You would be better
off buying a bigger and better UV sterilizer than adding salt to your pond. UV
sterilizers or Ozone will eradicate bacteria if used properly, better than any
salt solution will, this is a proven fact! It is also a proven fact that the
two pieces of equipment mentioned above will improve water clarity, redox
quality and lower TDS; salt on the other hand will do none of these.
Salt will
have no negative effects on an AFS at all and can be used in conjunction with
medication if need be. Like all medications, commonsense should be applied when
using a medication with any filter when that medication could or would
negatively affect the bacteria and the nitrogen cycle.
I do not know
who Duncan Griffiths is (I think he’s from the UK), but he would get an A+ in
my class for telling it like it is. He has but this article on the internet for
public viewing and I think it deserves merit in my blog so others can read it.
Excelsior,
Kevin
Disclaimer: This article is for educational
purposes only and not for monetary value. I do not warrant or assume any legal
liability or responsibility for its contents.
Salt and no vinegar: An overview on
salt, sodium chloride, by: Duncan Griffiths
Many
koi keepers have accepted salt in the koi pond system as therapeutic and have
used it on a day-to-day basis for many years. Salt is known to be a strong
bactericide and is used in many medical conditions both in human health care
and in small and large animal vet practices.
In
the koi hobby it is used as a prophylactic long-term additive to the koi's
closed circuit environment. It is
believed that in maintaining a constant low-level dose of salt helps with
stress in the fish, maintains a good immune system (stimulating mucus
production), and keeps bacteria both Aeromonas and Pseudomonas, to small
numbers. It also is believed to help keep ectoparasites low in numbers and
finally helps a koi dealing with toxicity from high or constant nitrite levels
or other chemical imbalances either internal or external. Whilst some of the
above points may be true some are not, and even some that do have some basis of
fact, there can however be equally logical reasons which make the case in the
opposite direction.
STRESS
It’s
a proven fact that salt does help with stress in koi; in the short term it's
very successful for this purpose. So one could draw the conclusion that it is
no bad idea to keep koi in a permanent low-level long-term solution. This is
not however the case. The koi should not be subject to permanent long-term
stress. This tactic just glosses over a basic inadequacy in the koi keepers
system, either poor husbandry or poor and inadequate filtration. In the short
term this is an appropriate course of action, above five to six weeks it is
not. A low-level concentration of salt in the long-term will not protect the
koi from a constant barrage of stress the koi will in the end succumb. But however if the koi's habitat has
excellent water quality there is no need for the salt being in place.
IMMUNE SYSTEM
The
koi's immune system is a very complex mechanism. The koi’s first line of defense from external threats is the
mucus layer of the cuticle, which is produced by the gills and by goblet cells
located in the epidermis. The cuticle contains antibodies, which help the koi
defend against disease. Also contained in the cuticle is unwanted debris from
the cells of the fish, which is what parasites find so irresistible. So one
could argue if we could stimulate the koi to over produce mucus we could
increase its immune system. The trouble with this theory is, there has to be a
greater understanding as to what circumstances cause the over production of
mucus. The koi can over produce mucus for a variety of reasons but to
demonstrate the point we will take parasitic involvement. When parasites
invade, it causes immense irritation to the koi. If on the first few attempts to be rid of this irritation
the fish is not successful the koi will begin to over produce mucus. This is an
involuntary action on the part of the koi. If the parasitic condition does not
resolve itself, which of course it may not, without medication, the koi will
continue to over produce mucus. The next step is the koi gets covered in the
familiar slime disease, but by now the koi’s immune system is going into
reverse. Why?
There
comes a point in the koi's battle against the irritation whilst it is over
producing mucus that the gill lamella gets clogged in its own mucus as a direct
result of the excessive production. This in turn impedes the koi's ability to
take in an adequate oxygen supply; the knock on effect of this is the koi gets
deprived of oxygen by its own making. When the koi's oxygen level drops the
immune system begins to degrade. Its ability to fight the parasite diminishes
and the parasite takes this opportunity to overrun the fish. The fish then gets
weaker and weaker until in the end it simply gives in and dies. Salt in a koi
pond is an irritation to the koi, which is why it causes over production of
mucus and this is the desired effect and reasoning for its continual use. If a
parasite is present without suitable medication to cure the parasitic
irritation the salt can make a bad situation worst.
I
have on occasion found salt to be the one last piece of the jigsaw that pushed
an already sick fish over the edge by further encouraging over production of
mucus, that in turn impedes the fish's ability to respire, plus, salt already
depletes oxygen, not by much but it is another factor in the koi's inability to
take up adequate oxygen. These factors all come together to finish the fish. So
you can see from this, to subject a koi to long-term exposure to salt is in
itself causing it long-term irritation and therefore a form of long-term suffering.
That’s the price of adding salt to get a*good* mucus layer and *immune* system.
Having said all that salt as a treatment for koi is usually more of a benefit. The type of drawback I have just
indicated of salt pushing a sick fish over the edge is rare but does happen on
occasion. And it’s a valid point that is worth bearing in mind when
contemplating the long-term use of salt.
LOWERING BACTERIA
The
case for lowering bacteria is a complex one and is open to many
interpretations. Many people say you can’t have a completely bacteria free
system for many reasons, this reminds me of a strain of bacteria that learnt to
survive deep on the sea bed around hot springs gushing up sulphur from
volcano's under the sea bed .
1.
In an ideal world even if the bacteria count in the water is nil there will
always be bacteria on the fish.
2.
The fish will always be producing bacteria in there waste product.
3.
You have air bourn contamination including bird droppings etc.
4.
Bacteria from plants in the pond the list could be endless.
It’s
a recognized fact that salt does kill bacteria, what types and how many, will
be the topic of many a hot debate. If you buy into the fact that salt kills
bacteria, you also have to buy into the fact that to keep salt in the pond on a
permanent basis there must be no half way measure's, that salt either kills or
it does not. (Salt kills all or salt kills nothing) if your uncertain what
strains are left and how many what was the point?
I know the advanced hobbyist will make it his mission in life
to find the answer to this question, but the everyday hobbyist will probably
never know. He will simply keep adding salt thinking this is an appropriate
course of action rightly or wrongly based on what he has observed some other
folks in the hobby do. A simplistic view true enough, but if you accept the
last few statements you could argue the fact it might not be possible to lower
the bacterial count with salt alone. BUT again it's not quite that simple. I am
reminded of a saying, "Man rules the earth" some say it’s the
“insect” others “mammals”. Make no mistake this planet belongs to Bacteria! The
bacterial evolutionary trail is impressive to say the least.
Bacteria
evolve to changes in its environment faster than any other organism; the
evolution time scale for bacteria when it is forced to adapt to change is
measured in a year or two probably less, not hundreds and thousands of years as
it is with the animal kingdom. We share this planet with bacteria not because
bacteria allow us; no matter how effective bacteria are at the survival game
our immune system is far better in most cases.
I
say most cases because we still have to live with bacterial strains that are
ever present and are a very real threat to humans and animals and our immune
systems have not yet learned to combat such strains. So it seems that bacteria
are better able to adapt in evolutionary terms than we are. With this in mind
you will have to assume that there will be bacteria in the pond system for
which salt poses no threat. And for the strains that are effected to constant
levels of salinity and do succumb readily, these strains did not magically
appear in the pond system and are likely supplied to the pond from readily
available sources on a continual basis. And upon entering the system and
continually meeting an opponent like salt, they should eventually adapt, and
ultimately overcome the very thing you put in place to stop them. If bacteria can overcome antibiotics,
bacteria can and should reign over salt.
PARASITIC CONTROL
Salt
has been used for eradication and control of parasites, well longer than I care
to remember, and it does seem by many to be very effective for this purpose.
Although personally speaking I have yet to find a case of parasitic outbreak
that salt has cured for ME[Ed: I also must agree here with this statement that
salt gives hobbyists a false sense of security.]. But then again the author is
known for taking a more direct approach to parasitic outbreaks thanks to Mr.
Potassium permanganate and Mr. Chloramine T. When using salt for parasitic control the salt acts like a
piece of blotting paper soaking up water, this process is called osmosis.
Osmosis and osmotic shock
Osmosis:
A
term for the transfer of a fluid through a membrane from a low to a higher
concentration solution. In ordinary circumstances in a fresh water system when
salt is added to the system lets say 0.6% salinity any fresh water of nil or
low salinity migrates to the higher salinity until the concentration equalizes.
However on occasion this appears to work in the koi keeper's favor for a couple
of reasons one of which will be discussed in the very next section. But from
the parasitic point of view, as salinity is increased in the koi pond the fluid
in the body of the parasite being of a lower value to the outside salinity
begins to migrate to the outside of its cell walls in an effort to equalize the
pressure difference. Thus dehydrating (crenates) the parasite, and destroying
it.
The
object of the game in this instance is to increase the salinity very quickly,
in fact as fast as the koi can withstand. So as to create an unequal
concentration between the inside body fluid of the parasite, and the
surrounding water. The cell cannot adjust in time to stop the loss of body
fluids. The same is also true of saltwater fish and its parasites but in
reverse. If you dip a saltwater species' suffering from parasites in fresh
water the fresh water migrates into the cell of the parasite, as the fluids of
the parasite is of a higher salinity, and as the parasite inflates with fluid
its cell wall is breached.
So
you could say the fresh water parasite implodes and the saltwater parasite
explodes. So from this you will observe that the key to parasite control is to
move upward in salinity as quick as is safe for the koi. If the occasion arise
to increase salinity slowly which is often the case with low permanent
maintenance salt doses the effect is lost. The protozoan has time to adjust
(exchanging its body fluid for one of a higher salinity). Additionally the
concentration difference is a lot less in a lower salinity, so a lot less
osmosis takes place. I have personally seen flukes, trichodina and costia
living quite happy and oblivious to the fact that their environment was 0.9%
salinity. The koi does not suffer from these adverse effects of salt osmosis
because of its complex osmoregulatory system, which sets up a defense against
the exchange of fluids. But there are circumstances in koi where this system
fails and that is the subject of further sections.
THE KOI'S OSMOREGULATORY SYSTEM.
The
koi has a very complex system for the exchange of salts, body fluids, the
intake of minerals, which it constantly exchanges and processes, the process
that controls all this is called the osmoregulatory system. Because the koi's
body fluid is of a low salinity and its natural surroundings even lower or nil
in terms of salinity, there is an obvious saline concentration difference.
Water moves into the koi via the delicate gill lamella membrane and membrane of
the gut. Also salt ions migrate out of the koi by diffusion via the gill
lamella. There is a continual complex exchange of salts and fluids in order
that the koi strikes a very difficult and even balance. The koi's kidney is super-efficient and
replaces lost salts by reprocessing and reabsorbing salt from urine and trace
salt in the pond system. The koi is also balancing its own pH in the blood
stream. The gill will exchange hydrogen and bicarbonate ions in exchange for
sodium and chloride ions, in order to take up and renew lost and utilized salts
from its surroundings and stop its blood pH from dropping by the accumulation
of bicarbonate and hydrogen ions. This may be an explanation of why people say
a high pH is not good for koi It might be the case that the koi cannot dump
hydrogen and bicarbonate ions into an already saturated system with high pH. This
is a very brief look at osmoregulation it will be touched on in later subjects.
OSMOSIS IN KOI
As
already stated the koi lives with osmosis every day, it's a natural occurrence
in the day-to-day life of a koi. But there are a couple of instances when it
becomes unnatural, and when this results it’s called “Osmotic Shock” and can
and will result in fish death. Take an everyday koi swimming in an everyday
pond none saline (typical salinity of tap water 0.05% or lower) so this could
be classed as a typical, none or very low salinity pond environment. As
previously mentioned the koi lives with a natural osmosis taking water on board
into the blood stream and tissue extracting natural elements as it goes about its
business. After the kidney has finished processing these elements, this fluid
it is excreted mainly via the gill (ammonia), much as animals and humans
excrete waste body fluid.
The
reason for this is the koi's body fluid is 0.9% salinity or = to, 1.5 oz. per
imp gallon salt. To put it into
terms easier to understand, the fresh surrounding water try’s to equalize the
concentrations from low to high (external to internal) or you could say the
koi's higher concentration body fluids draws the fresh water into the body to
equalize the concentration. Also because the body is 0.9% saline the salt migrates
out of the koi to a non-saline environment (diffusion), so the koi is
continually losing body salts and exchanging fluids. This is a continual
process 24 hours per day, and again an involuntary action.
THE BENEFITS OF MANIPULATING
OSMOSIS AND OSMOTIC SHOCK
However
if the fish has an open wound or a deep ulcer, this provides an uncontrolled
entry point for the water to ingress to accomplish the equalization process,
the fish has no control over this event should it arise the koi's
osmoregulation system has to try to cope.
OSMOTIC SHOCK
The
rapid induction of water into the koi's tissue and blood stream means that the
koi's kidney has a very heavy load placed upon it, as it now has to process
excess and waste fluids. Eventually the kidney's function is impaired, and the
influx of water can't be coped with. Then the fish begins to bloat and swell
with bulging eyes (dropsy). However if you raise the salt concentration in the
environment (water), you reduce the amount of water entering the fish which unloads
the kidneys.
At a water concentration of 0.9%, the
inflow of water thru the ‘hole’ is greatly reduced. You are equalizing the
concentrations internal and external to the fish thus decreasing the amount of
water entering the body (less osmosis taking place) giving the fish time to
heal and close the portal of entry for the water (the ulcer or damage). There is another situation in which
osmosis takes place in koi which does not require an additional entry point,
and that’s bacterial or viral dropsy.
When
a viral or bacterial infection compromises the major organs and kidney, and
either impairs the kidneys function, or shuts it down. This stops the koi from
ridding itself of excess waste fluid. In the case of virus there is little that
can be done, as there is no recorded and confirmed cure for virus. But for bacterial infection however
there is. The koi should be supported with either antibiotics or salt and/or
roflavine hemesulphate. And salt at 1.0% .This therapeutic hypertonic dose of
salt draws the excess fluid back out from the fish, whilst the antibiotic or
proflavine sets to work on the infection to get the kidney functioning again if
not too much damage has already been done.
With
these two conditions salt is indeed the weapon of choice with whatever topical
remedy works for you.
When a koi is in stress it
will lose body salts.
Ordinarily
this is a normal event, but because the koi is stressed its kidney will not
replace salt by process from its normal sources.
From
all the above it is also easy to see why salt used as a stress aid does work. As
a slightly hypotonic salt solution in the pond water will greatly reduce the
koi from losing salts, and stops the osmotic effect on fluid induction.
1. A
salt solution equal to the koi's own saline concentration is said to be
isotonic.
2. A
salt solution greater than the koi's saline concentration is said to be
hypertonic.
3. A
salt solution less than the koi's saline concentration is said to be hypotonic.
AMMONIA AND NITRITE
When
a filtration system breaks down and toxins are not processed as would normally
be the case, or a new virgin filter is being cycled, we can normally expect to
experience high ammonia or nitrite levels. This will soon have a negative
effect on the koi if left unchecked. As these levels take up to 6 weeks to
subside, we then have to consider other ways to help the fish deal with these
toxins in order that the koi survives, and salt can go a long way to this end. A
well-salted pond protects the koi in a few ways. First off when dealing with
high ammonia salt helps the koi over produce mucus, and this offers protection
in the short term from, ammonia irritation and ammonia burns. I say short term
because ammonia normally subsides in about ten days or so. By then the nitrite
is on the way up to dangerous levels and this will take the rest of the afore
mentioned time span to abate.
Nitrite
toxicity affects the koi by altering the hemoglobin in the koi's bloodstream,
affecting its capacity to carry oxygen. If a koi hemorrhages whilst suffering the
effects of nitrite toxicity it will be noticed that its blood will be brown
instead of bright red (brown blood disease). Salt helps with this condition
because the Chloride anion competes with the nitrite anion for entry into the
gill lamella, thus alleviating some or most of the toxic effects. Plus it will
also help the koi deal with the stress and fluid loss whilst dealing with this
dilemma.
SALT IN THE FILTER
Upon
introduction of salt into a filtered system many people say that salt does not
affect the helpful bacteria in the media. This is both true and untrue to a
curtain extent. A salt solution of 3.0% will destroy all filter bacteria but we
do not use these concentrations in the koi pond
Salt
added at 0.3% or 0.6% or 0.9% or even 1.0% although perceived to be of no
effect to filtration bacteria will in fact destroy curtain types of bacteria in
the filter. But equally there are types of bacteria in the filter that salt at
these levels will not affect, and these will pull in the slack. As long as the
salt is added slow enough. As with all things in life there is no gain without
some pain.
KOI COLOUR AND SALT
It
has been documented that constant exposure to low-level salt will dull out the color
in koi by acting on the pigment cells called chromatophores found in the dermis.
SALT TREATMENT PROTOCOLS
Short-term
treatments
Short-term
treatments of salt in the koi pond should be limited to
1. 0.25 oz. per
imp gallon (for stress)
2. 0.5 oz. per imp
gallon (parasite control or
bacterial infections) this also causes the fish to over produce mucus and as a
result some parasites get sloughed off with the excess mucus
3. 0.75 oz. per
imp gallon (parasite control) (not recommended for pond treatments quarantine
only)
4. 1.0oz. per imp
gallon (not recommended for pond treatments quarantine only)
For bacterial gill infection or dropsy
(extra O2 always)
Always
make sure the salt is well dissolved and never put the full dose in at once Divide
dose into 4 equal parts and Spread it out 12 hours apart to avoid shock to the
koi. Equally never drop it as quick if anything take it a little slower there
is no mad rush, in fact there is a little table at the end of this paper to
demonstrate just how hard it is to get out of the system once in there.
DIPS
Caution
here! Dips are extremely stressful
on the koi, as they mostly tend to be of a very high hypertonic concentration 3
oz. per imp gallon for 5 to 10 minutes very effective for cleansing the gill
and for parasite eradication and bacterial infection. Warning! If the koi rolls
over during this treatment don’t panic but return the fish to the pond
immediately, where on it might still stay on its side but be assured it will in
half an hour or so start swimming again with no ill effect. There are higher
hypertonic doses than this but I do not recommend them although I have
practiced them.
TABOO’S AND SALT (UNDOCUMENTED)
SALT AND POTASSIUM PERMANGANATE
There
are many do’s and don’ts with salt, and one of which is salt and potassium
permanganate should not be mixed. This is not the case they are perfectly
compatible, I have however read of cardiac arrest in koi when these two treatments
are mixed, but have not seen or heard of a single case to relate to you here. But
it must be born in mind that each of these two treatments in it’s their own
right depletes oxygen, so extra care is needed.
SALT AND FORMALIN
I
have many books that say that these two cannot be mixed and yet nobody gives
good reason for this statement. I know many, many, people that treat with
formalin and salt with no ill effect including myself so I am speaking from
personal experience, as long as the salt level is below 0.3 oz. per imp gallon
and extra oxygen is administered during the treatment all should be ok. As
formalin is probably the best oxygen stripper there is. But your heart will be
in your mouth the very first time you try it if memory serves.
ANAESTHETICS AND SALT
It
is said by many that anesthetic and salt should not be mixed some of this is
also not true and personally I use
benzocaine and have on many occasion used it with salt with no effect either
before during or after the anesthetic. However MS222 should not be used with
salt. But the strange thing here is that MS222 is the water soluble version of
benzocaine, so go figure. Oil of cloves I cannot comment on as I have only on
rare occasion had to use clove oil, but some experimentation might be called
for.
Basically
as far as I am aware there are virtually no mixtures that cannot be achieved
whilst using salt, apart from two or three exception listed here that can’t be
substantiated, but you might want to tread a little careful if you should
decide to try these for yourselves.
SUMMARY
Now
you may have formed the opinion that the author is very anti-salt. You would be
very wrong. I just believe that there is a time and a place for almost
everything and everything in its place. Its true I do not keep koi in salt
permanently just because I can, and it * seems * like the appropriate thing to
do. Koi were born to live in a non-saline environment and only live in saline
by human intervention, but if you want to keep them happy and healthy salt is
not part of the equation in the long term, short term is a very different
matter.
There are lots of occasions that salt is
very appropriate and indeed is the only course of action. Just learn to
recognize those moments in time when it is needed. Then go for it. All I have
really tried to do here is lay out some basics and some explanation, as simply
as I can so as the not so experienced and newcomer to the hobby can judge for
him or herself whether or not and how salt is going to be used. Based on a little more data than. “My
mate uses it and swears by it!”
I have tried to explained the why’s and
the when’s and the why not’s, so as we can make an informed choice as to
whether or not to use salt and how to. And ultimately that choice is always
going to be yours not the koi’s. For those of you that can and will use salt
and think it’s a piece of cake to get out of the system with a couple of
partial water changes once in there. This last section on the following pages is just for you.
Thank
you for taking the time to reading this my first koi paper.
Duncannegar
An overview
on salt, sodium chloride, by Duncan Griffiths
Many koi keepers
have accepted salt in the koi pond system as therapeutic and have used it on a
day-to-day basis for many years.
Salt is known to
be a strong bactericide and is used in many medical conditions both in human
health care and in small and large animal vet practices.
In the koi hobby
it is used as a prophylactic long-term additive to the koi's closed circuit
environment.
