By Bob Goemans
Let’s begin by being very honest – how many
reading this article really quarantine their new arrivals? Probably
very few, and that’s quite sad in some ways- but understandable, as many marine
hobbyists are not fully aware of the pitfalls their fish incur from the time of
capture. Nor do they understand the association between parasites and
their host, whether in the wild or in closed systems (a.k.a., aquariums).
Fish can live in the wild with various parasites
and continue to function normally and look healthy. In fact, many
parasites have a special relationship with their host and are simply very happy
maintaining a small population of their species without damaging the host.
Simply put, the environment, i.e., salinity, temperature, nutrition, and/or
stress level, is satisfactory for both host and parasite to remain healthy and
continue their ‘balanced’ relationship.
But it all ends there once the fish is captured,
as the balance swings in favor of the parasite! Once captured, the “fight
or flight” response comes into play where all built-in survival strategies are
routed to escaping. The fish then shuts down all non-essential processes
such as digestion and the immune system for immediate use of energy for the
purpose of escape. And no fish, no matter how well cared for from time of
capture to arrival at your doorstep are as good as they were in the wild.
They are stressed, usually starved, and have been held captive in many different
and questionable water conditions of which none come near the pristine quality
of their natural surroundings. So, no matter how good the fish looks, it
isn’t a happy fish!
In addition, the approximate ten days to two
week relocation process from the wild to your aquarium is just about what
parasites need to take advantage of this “window of opportunity” to increase
their numbers. Furthermore, wounds incurred from collection and/or
unsuitable tankmates during relocation are another problem, as bacterial
infections often begin in this time period.
Even if fish arrive looking like it is in
excellent health, it’s not, and there’s no doubt that the conditions in your
aquarium are not going to be what they were in the wild. Without a doubt,
the new arrival will have a smaller world, different mates, different
foodstuffs, and reduced water quality to name just a few. And, past stress
levels have given any existing parasites the favorable conditions to begin
expansion of their numbers. The result could be a very good chance of a
disease outbreak looking for a place to happen, and that would probably be in
Therefore, excessively politically correct
aquarists always say to quarantine all fish before placing them in
your aquarium. In my opinion that’s something like saying “don’t get out
of bed in the morning because you may have an auto accident on the way to work.”
That’s just not the way it is in the real world! The real question to ask
when it comes to the value of quarantining new specimens is “Does quarantining
increase chances of success?” In my opinion it most certainly does, especially
if quarantine facilities are not available at the shop where the specimen is
being purchased. And if so, then there’s no telling what disease,
parasite, or unwanted organisms could finally show up in your aquarium if the
new addition is not quarantined.
Small quarantine tanks, such as this
10 gallon tank with all the fixings so to speak, are often available
through better local shops for less than 100 dollars! Photo By Bob
Now, that may sound like I’m being
excessively politically correct. However, I’m not saying it is a "must"
procedure or that it’s my only stance on the subject. Other considerations
need be looked at, such as your level of disease/treatment knowledge, time and
space to accomplish quarantining, and the source from which the specimen is
coming from. Furthermore, it should also be said that quarantining does
not guarantee something unwanted won’t slip by and get into the main system.
Nevertheless, it does ‘greatly’ reduce that possibility! And the bigger
and more complex your aquarium, the more you have to lose if you do not
quarantine the new specimen. And as for those that say only healthy fish
are purchased, therefore there’s no need for quarantining, I say how can you be
sure it’s not a carrier of an internal parasite? And do you realize that
there are far different cycle timeframes for internal and external parasites to
either be seen or have a negative effect on its host? Therefore, even if
the fish looks healthy, the “Dump and Pray” method is quite perilous.
Even though the quarantine tank is just that, a
small environment that can house a new fish in somewhat comfortable surroundings
while its owner makes sure it’s free of any maladies, it can also be easily
turned into a treatment tank/hospital tank. And if it goes that road, the
most common external parasites are Cryptocaryon or Amyloodinium,
where the usage of copper is by far the most useful treatment regiment. By
the way, there are two different types of copper treatments on the market— Ionic
and Chelated, and it’s a good idea to understand the difference between them.
Ionic Copper, i.e., copper sulfate, is generally
referred to as free ionic copper. It does not stay in solution very long
since it quickly precipitates, mainly as copper carbonate. In fact, in an
aquarium that contains a calcium carbonate substrate, about 50% of the copper in
solution will be absorbed by the carbonate material within the first two hours.
Another 20% is absorbed over the next twenty-two hours. Therefore, 75% of
the initial copper treatment solution is generally unavailable at the end of the
first day of treatment (Cardeilhac & Whitaker, 1988). Hence careful and
frequent attention must be given to the therapeutic level of ionic copper since
it is constantly depositing or bonding itself to substrate, rock, dead coral,
etc. Dosage rate for most fish are .15 to .20 ppm.
Chelated copper medications
are also available and stop or slow copper from precipitating out of solution.
Their copper is bonded with various compounds that solve the problem of having
to closely monitor its level and apply additional dosages. Depending upon
the brand used, dosage level will either slightly or greatly exceed .2 ppm.
Nevertheless, the dosage rate with a chelated product is tied to the volume of
water in the tank to be treated, and if that volume is misjudged, the treatment
can either be ineffective or dangerous to the animals being treated. And
only a test kit made by the company selling the chelated copper should be used
to obtain accurate readings.
From the above descriptions, it may appear that
chelated copper is easier to use, however, I prefer ionic copper since it can
easily be monitored with any brand test kits and a precise dosage level
maintained, even though there’s on-going attention and additional dosages.
Nevertheless, whatever type copper is used there are some precautions as its
necessary to remove chemical filtering media prior to using it, as it would
remove the medication. Copper will also disrupt biological filtration,
therefore its necessary to keep a close watch for an ammonia spike.
Furthermore, long-term unnecessary copper treatments suppress immune systems,
making fish more susceptible to other pathogens which is also a good argument
against using a chelated product as treatment levels can vary. Also, keep
in mind some Angelfishes, Blennies, Butterflyfishes, Cardinalfishes, Dragonets,
and Wrasses exhibit sensitivity to copper. And since copper increases the
animal’s mucus covering, dragonets may suffocate since they normally have a
heavy coating of mucus. Thank goodness Cryptocaryon or Amyloodinium
rarely affects them.
Keep in mind that copper treatments are
ineffective when it comes to external parasitic worms, therefore products
containing formalin are quite useful, and there are many commercial
formalin-based products on the market. And their dosing instructions must
be carefully adhered to. Yet bear in mind the effect ammonia has on this
product, as it reduces its effectiveness, therefore lowering its impact on the
organism to be treated. Because of that, it’s always wise to keep an
exceptionally clean treatment environment by not allowing any detritus and/or
uneaten foods to remain. And frequent water changes are also advised,
along with maintaining the therapeutic treatment level.
The treatment for internal parasites is more
complex, as they usually do not manifest themselves early enough to be treated
in a quarantine situation. In fact, it’s necessary to identify the
parasite, then treat with specific chemicals to target that known parasite.
Yet, it’s still feasible to see the results some internal parasites may have on
their host if maintained in a quarantine situation for 30 – 40 days. If
so, then, depending on the problem area and the identification of the parasite,
a specific treatment regiment can begin. As for bacterial infections, the
quarantine/hospital tank situation is the ideal area for treating these type
problems. Better to treat it here than in your main show tank.
When it comes to the length of time spent in
quarantine or hospital tanks, it should be recognized that treatment is usually
only successful at a certain timeframe in the parasite’s life cycle. And
since we cannot accurately judge when one portion of the cycle begins and
another ceases, its better to treat for the length of time the entire cycle
encompasses. Those cycle times can sometimes be found on various websites
by simply putting the name of the disease into your web search engine and
reading the applicable articles. I should also add that timeframes could
be affected by conditions such as temperature and salinity. Yet, a period
of at least 30 days, preferably 40 days in most cases, is reasonable in my
Furthermore, quarantine is not only a subject
matter that concerns fish, as live rock, live foods, and even natural seawater
should get some consideration. As for fishnets, they are the easiest to
disinfect and also the easiest way to transmit diseases between aquariums.
For those with more than one aquarium it is wise to sterilize the net after each
use or at least have more than one net and use each on the same aquarium.
A little household bleach in a bucket will do a nice job of sterilizing a net.
Simply dip the net and flush it with freshwater. Don’t leave the net in
the bleach water, as most will quickly deteriorate. As for live rock,
first cycling it in a separate container such as a plastic garbage can will
easily reduce its nutrient content, and give one an opportunity to further
inspect it for any unwanted animals or algae growth. It doesn’t guarantee
a mantis shrimp or unwanted bristle worms or alga spores won’t make it into the
main show aquarium, but the chances of that happening are greatly reduced.
Also, associated nutrients from die-off of small animals and plants are left in
the cycling container.
There are also those that feed their marine fish
live foods, e.g., goldfish, mollies, guppies, and even small live shrimp.
What I’ve seen of this live food in some aquarium shops is that it’s health and
nutritional value is highly questionable. What better place could they be
placed than in a small ‘quarantine’ freshwater or marine aquarium where they can
be fattened up and made healthier before being used as live food.
As for freshly collected seawater, it should be
used within twelve hours of collecting. If that’s not possible then other
precautions need be taken as seawater can quickly become toxic due to the quick
die-off of its plankton. Keep in mind that freshly collected seawater may
look perfectly clear, yet it actually teems with microscopic organisms.
These tiny organisms, animals and plant wanderers commonly called ‘plankton,’
will die-off when their food supply, usually each other, is consumed. The
result can be an ammonia-laden soup. If the freshly collected seawater can
not be used quickly it can be stored in sealed plastic or glass containers in a
dark area for up to two weeks. Darkness simply prevents unwanted algae
growths. Prior to its use the die-off on the bottom of the container
should be removed and the water aerated for 24 hours. Try to collect away
from inshore areas where sewage, fertilizer, insecticides, heavy metals and
other pollutants tend to collect.
As for seawater storage, a long-term reader
suggests adding one bottle cap full of regular household bleach to fifty gallons
of freshly collected seawater and then aerating for two days. Then
allowing it to settle for a day, then vacuuming the sediment from the bottom of
the container. Then aerating again for one day and/or until no smell of
bleach remains, then storing/using as needed.
In all honesty, it’s not unrealistic to expect
good results in treating the show aquarium if a disease breaks out in a
‘fish-only’ system. Nevertheless, practicing good quarantining procedures
initially, in my opinion, is the way to go. And that quarantine tank can
be as small as a 10 gallon aquarium having an external biological filtration
system, strong aeration, and sufficient decoration. Simple decorations
such as artificial rock will help make the new fish feel somewhat at home while
in the transition mode. Of course, size of this aquarium depends upon the
size of the animals to be quarantined. And if a sandbed is desired, use a
non-calcareous medium incase copper treatments become necessary. Additionally,
the ‘quality’ of the water in the quarantine tank should be equal to that in the
show aquarium, i.e., same pH, salinity, and with no ammonia and nitrite.
While in this temporary home should a serious parasitic or bacterial infection
occur, the tank could be transformed into a hospital tank.
Where fish are concerned, the choices are clear:
dump and pray; quarantine; or, have the local dealer hold the specimen for at
least ten days while the animal has a chance to regain some of its stability.
For those of you that want to “save” the fish from the local shop’s tanks, if
they are that bad, the three choices are now reduced to one –
quarantining! Those purchasing through mail order have only the first two
Early detection, accurate identification, and
correct treatment regiment. Quarantining is easier said than done, but
well worth the effort! Sadly, most hobbyists continue to use the "Dump and
Pray" method. Let's hope that more hobbyists embrace a quarantine protocol in
their husbandry routine!
quarantining b/f's and mandarin? 6/8/11
I will be receiving 3 B/F's and a Mandarin Fish mail-order later this week. I
have a 30g quarantine tank ready to go but have a couple of questions.
Would it be best to do a PH-adjusted, freshwater dip w/Methylene Blue, on the
Mandarin and place him in my established 125g FOWLER tank?
<Yes; this is what I would do; not quarantine this family (Callionymidae) and a
few other fish groups, unless there was something apparently "wrong" with them>
After reading most of the FAQ's on these fish, I realize they are not as
susceptible to Ich but I am quite paranoid about its (Ich's) re-introduction
into my tank as I have battled it on and off for two years (luckily with me
winning or more likely in a stalemate with the enemy!) with no loss of fish.
<Mmm, well... up to you>
On to the B/F's! I'm getting a Tear-Drop, Pakistan and Black-Backed. I realize
these fish are quite sensitive and will most likely start eating prepared foods
and re-build their resistance once placed in the main tank, but would a week or
so in quarantine then a freshwater dip w/Methylene Blue or Formalin (safe for
<Toxic, but if they're in "good shape", likely worth using>
be better for the fish than acclimating them, freshwater dipping them and
immediately placing them in the main tank?
<I would likely quarantine these, given your system (the 30)>
I've read about every FAQ's on B/F's and added to them with some of my questions
in the past but I am on the fence here on whether to quarantine or not.
<Me too/I as well>
Even though I have run my tank fallow for several 8-week periods over the last
two years I know I still have some entrenched Ich. The last time I added 4-week
quarantined B/F's I had an outbreak but decided to treat with Selcon soaked
Spectrum flakes and Spectrum Thera-A pellets. The fish kept the cleaner shrimps
very busy, but all came through and continue to thrive.
My point is, quarantining or not, with my particular tank, probably means a
small outbreak of Ich once new fish are added.
Lastly, even though the HOT refugiums are small, about 3-4 gallons, would you
recommend one for pod growth for the Mandarin or am I wasting my money?
<Are worthwhile. Even what appear to be small volumes of "live" sand, other
substrates, macro-algae, a very considerable amount of life is produced>
Thanks in advance for all your insight and wisdom. I spend most evenings
perusing your excellent site and wish you all lived closer so I could buy you a
beer or two!
<Oooh! Let's hope we meet! Bob Fenner>
Anthias and Wrasse harems
I currently have 4 Bartlett's Anthias in a 29 gallon QT tank.
<Mmm, need more room by this by far... Will be both psychologically and
socially, let's combine the two terms, psychosocially too cramped in a very
They have been
there for a week and all seem to still be females. For the first couple days all
of them were eating and swimming around. Now one is hiding behind the powerhead
<Oh, already. See, I did state "in a very short while">
in the tank and not eating and another has a pretty beaten up tail fin,
but is still swimming around and eating. My assumption here is that there is
some jostling for dominance going on,
<In part, yes>
but I don't want it to be at the expense of a couple of them dying.
<Which they will if not moved>
What can be done to help this situation?
Do they need to be partitioned or separated in some way?
<Not in this volume, no>
The Anthias are going into my 210 gallon upon completion in QT.
<Anthiines are one of my "generally don't quarantine" groups/families of
fishes... They suffer too much from the delay, compared with simple dip/bathing
and expedited placement in main/displays. Is this clear to you?
Like most Gobioids, Blennioids... much more of the time these fishes "die
mysteriously", jump out, starve, beat each other up... I'd place them in the
larger system, stat.!>
This carries over into the harem of Flame Wrasses I just purchased them today
and put them into a different 29 gallon QT tank.
<These two I'd dip (pH adjusted freshwater... detailed on WWM:
and the linked files above)>
The harem consists of 1 male and 3 females. I want to make sure I don't run into
the same problems
I am currently having with the Anthias.
<Similar, yes... Move these Jordan's Cirrhilabrus>
The only decor in either tank is a few PVC pipes, a heater, a powerhead, and an
Thank you in advance for your assistance!!
<Certainly welcome. Bob Fenner>
Re: Anthias and Wrasse harems– 03/19/11
Thank you for your help. I figured you would say to move them over, I just
needed you to push me over the edge to do it. I really don't like not
<Ahh; is at least a two-sided saber>
I think going forward I will have a 75 gallon quarantine tank when introducing
groups/harems so that I can
quarantine (not for the 210, but when I upgrade). Would this be sufficient or
should I not quarantine in any size tank really?
<... not certain species...>
<Another welcome. BobF>
To quarantine or not to quarantine... that is my question 4/16/07
Aloha boys and girls. My name is Alex (and I'm an addict...?)
<Sounds like you're ready for our 13 step pet-fish program... the thirteenth is
where you turn around and go back to number one!>
and I would just like to thank you all for giving your time to this wonderful
resource. I owe much of my success in this hobby (just passed the 3 year mark
with a beautiful sps dominated tank) to all of you for answering the questions
posed by others and posting them for us all to read.
<Ahh, tremendously pleasurable to realize>
I myself am a long time reader but this is my first time writing. My question is
this. I've just ordered a Blue Tang (Paracanthurus hepatus) from Live Aquaria
and was wondering if what I read was true? Like I said I'm an avid reader
(daily) of your wonderful site and I remembered reading a while back an article
regarding acclimation on this particular fish. In your article Paracanthurus
hepatus, the Pacific Blue Tang of Many Names you say not to quarantine this
<This is my standard assertion re this species, several others... But some of
the rest of the Crew here are more "strict" concerning carte blanche acclimation
of marine (et al.!) livestock>
Under the Introduction/Acclimation section of this article you state to just do
a PH adjusted freshwater dip and than add the fish to the main display. Is this
<Yes... unless the specimen/s (including other species in the same shipment)
show obvious behavioral and/or parasitic anomaly>
Is this still your opinion?
<Yes... with the above qualification>
I'm a true believer in using a QT having never lost a fish or had any issues and
have a 30 gallon up and running for this purpose.
<Good. A good size>
I'm somewhat in agreement that the stress involved in moving the fish from one
tank to another may out weigh the benefit of the quarantine but is it worth the
risk of possibly introducing ich or some other pathogen to my well established
Thank you for your time (YOU GUYS ROCK),
<Mmm, well... where/when in doubt, I default to the more conservative end of
actions, considerations... Do quarantine the new Tang if you would like (along
with FW dip/bath) enroute to the QT... For myself, having handled many specimens
in commercial settings, much more likely/often the dip/bath alone is more
efficacious. Bob Fenner>