What is a Quarantine
tank?
Ideally, it is a miniature version of your pond. This includes
proper aeration and filtration, with frequent water changes.
The size of a quarantine tank depends upon the fish load.
It could be as small as 50 gallons for one or two small
koi, or as large as 1000 gallons or more if it is to hold
several large koi. The important thing is that it must be
capable of maintaining near-perfect water conditions.
Filtration for a Quarantine
tank.
The filter need not be as sophisticated as the one commonly
used for a larger pond system. Small filters can be obtained
at a reasonable price from pond supply or garden supply
shops. It should include both mechanical (to remove solids)
and biological (to remove ammonia and nitrites) capabilities.
In larger quarantine systems the mechanical and biological
systems may be separate units.
The tricky part here
is biological filtration. As you may know by now, it takes
several weeks for a bio-system to "set up". Certain
types of bacteria must be present to convert ammonia to
nitrite and nitrite to relatively harmless nitrate. The
fastest way to quick-start a bio-filter is to use some media
from your existing system. Commercial bio-system starters
have not been proven effective, and are not recommended.
Many hobbyists keep a quarantine tank active throughout
the year by keeping a few koi in it. This keeps the nitrifying
bacteria active and capable of colonizing quickly with the
addition of more fish.
You should run your
filter with a pump capable of circulating the water once
every 30 minutes. If you use a submersible, please place
it in a net bag to prevent injury to the koi, who could
scratch themselves on it's sharp corners (when a koi is
in an unfamiliar territory, it will tend to dart around
nervously for the first day or so) Also be sure to use GFCI
electrical connections.
Adding a pond
koi to your Quarantine tank.
It is good practice to place one small koi from your pond
into the quarantine tank with the new additions. This will
expose whatever you have in your pond to the newbies, and
also will expose your pond to whatever the newbies may bring
with them. Better to discover any incompatibilities now
than later!
Water changes.
Due to the higher fish load in most quarantine systems,
it is important to do frequent and large water changes.
In an extreme situation, where biomass is not available,
one could actually maintain a quarantine tank with no filtration
if proper water changers are conducted. This would require
a 50% water change daily, and regular testing for ammonia
and nitrite so changes could be increased if called for.
With a proper filter, however, 10 to 15 percent changes
twice weekly is recommended.
In either case, you
should obtain test kits for ammonia and nitrite. Both of
these should be maintained in the zero to .1 ppm range at
all times. You should use water which has been de-chlorinated,
either by aging or by the addition of sodium thiosulphate
at a rate of 1 tbsp per 500 gallons for Chicago area water.
Feeding in a Quarantine
tank.
The general thought on feeding in quarantine tanks is
that if you are feeding at all you are feeding too much.
The point here is that food is the source of most quarantine
problems. A koi can easily go two weeks or more without
food. You should not feed your Q-tank fish for at least
two days after set-up. After this, very small portions of
food once per day will be sufficient. Don't forget to test
for ammonia and nitrite. If these levels begin to rise,
stop feeding immediately.
Medical care.
So what happens if the koi-in-quarantine develops health
problems? Immediate care must be provided if this fish is
to survive. If you are able to diagnose the problem, treat
according to recommended methods. The entire quarantine
tank should be treated, as both parasites and diseases will
easily spread to other fish in the system. If you are unable
to diagnose the problem, contact someone who can.
Phone numbers for the
MPKS Koi Health
Advisors are in every newsletter, or contact
Dr. Chris Shirkey, a local aquatic veterinarian, at
815-254-9115, or cell# 815-922-3566.
Probably the safest
and most effective over-all treatment for quarantine fish
is salt. It will kill or at least slow down most
parasites, and will also ease the stress level of the koi.
If you choose to use salt as a therapeutic, add non-iodized
salt at a concentration of 3 lbs per 100 gallons of water.
This gives slightly more than .3 ppt salt. Don't forget
to replace the salt at this same concentration with water
changes.
How long to Quarantine?
This depends on the condition of the fish, but generally
it is recommended to quarantine from 3 to 6 weeks.
If all looks good at this point, the fish may be transferred
to your pond. With the recent threat of KHV, some have recommended
quarantine periods of 6 months or longer.
The best way to test
for KHV is to raise the temperature of the quarantine tank
to 80 degrees and hold it there for three days. This
will generally cause a KHV breakout if your fish has been
exposed to it, however there is no guarantee, as some koi
may be immune KHV carriers. This is another reason why you
should have a small koi from your pond in the Q-tank (hopefully
not one of your favorites) - if you bring in an immune KHV
carrier, it can still infect another fish.
Happy Koikeeping!
©
Bryan Bateman 2006
