Many people have the concept that the aquarium
is a sterile and safe environment, and that safety seal is temporary opened
when you add new fish and plants into it. After that if your fish continues
to be fine and healthy, then no baddies like disease or parasites or bacteria
has breached the castle, until the next time you introduce new fish into your
In fact, that concept is very wrong!
All fish carrys bacteria/parasites on their
body, and indeed all aquariums contains harmful bacteria and parasites. This
is the same case as us humans. We carry millions of bacteria and parasites
(ie dust mites) on our hair and skin. We pass them around when we come into
contact with one another and when we come into contact with the things around
us. Look at our cash and coins. They change hands from one person to another.
Along the way, it has definitely ever come into contact with even strongly
contagious diseases. And they never gets washed! When is the last time you
wash your dollar notes? And do you know there are people who put coins in
their ears until they need to use them? In fact, the only time money gets
a rinse is when someone accidently drops them into the toilet bowl, after
with the cleaner digs it out with his mop that he use to clean the toilet
bowls as well as the taps you wash your hands with. Ok I think we've sidetracked
enough, but I guess you get the idea. Humans and fish actually lives with
bacteria and parasites as part of our everyday life.
These bacteria and parasites are kept in check
from doing the harm they are capable of by our body's and our fish's own defense
mechanisms. They are harmless unless the conditions becomes favourable for
them, thats when they can cause serious trouble.
Look at humans, our defense is down when we
suddenly put ourselves in very cold environment without proper clothings.
We can also get infections when we get physically wounded.
For fish, they are also very similar.
Fish's defense is down when:
Fish is under stress, causing the immune system to be
Poor water conditions such as sudden changes in water
conditions or water parameters
Physical injuries such as bites or scratches.
If left untreated, a sick fish acts as a fertile base for
these bacteria/parasites to multiply in large numbers. As a result, the infection
gains power and this infection then spreads to other tank mates. Over time,
your tank becomes a death trap killing everything in it.
Prevention is better than cure, and these words of wisdom
are never more true then when it is applied to fishkeeping. When you get a
disease, the first headach is identifying the disease. A wrong identification
will not only waste your time and money in giving it the wrong treatment,
it may even make matters worse. Other than that, medication can harm your
biological filter, and it can can trapped in your porous filter media, permanently
If you didn't skip the section above, you'll know that the
best way to fight the war against terror is to keep your fish in their best
conditions and help their immunity systems do what they do.
1. Ensure the water condition is kept to the ideal level.
Test your water with test kits at the first signs of
trouble (ie fish behaving abnormally, inactivity etc). Check for pH levels
and ammonia, nitrites and nitrates to see if they are under control. Early
detection of these problems give you a chance to rectify things easily before
it gets tricky (ie fish falls sick).
pH can be easily adjusted if it got too low or
ammonia or nitrite spikes can be easily diluted by water change (after which
your filtration system should be analysed to see what went wrong.)
2. Don't accidently add already sick fish into
To spot sick fish in the fish shop, sick fish usually have
the following symptoms
abnormal swimming style
(such as tailspin, rapid/jerky movement or misalignment).
In a fish shop, it is usually easy to spot problem fishes if you look at
the whole tank without concentration on one single fish. These fishes usually
do not move the same way with other fishes in its tank.
Signs of injuries to fins and body.
( such as bleeding, ulcers, skin or fin tear)
Skin/fin tear are usually caused by territorial fish fighting with one another.
In most cases, these injuries can heal rapidly. However, in such cases we
should think about its injuries and why it is injured. Aggressive fish often
fight and cause damage especially in a small enclosed environment. If only
one fish in the tank is injured but the rest of the fish are relatively
injury-free, then that fish may have been picked upon because it is already
weakened by some kind of sickness and the other fishes have sensed it.
( ie not eating )
A healthy fish will devour any food without much thought. A loss of appetite
in the short term when a fish is introduced into a new tank is normal. This
is due to the stress of new, unknown surroundings for the fish as well as
a new feeding pattern by different keepers. However, if a fish is to suddenly
stop eating in the same tank it has always been in, it is highly possible
that it is sick. If you are aquiring an expensive fish or if you know the
fish store well, you could request to see the fish eat before buying.
(note: Be tactful! Don't say '"I wanna see your fish eat because I
think it may be sick." Instead say something like "I love to see
fish eating.. can I feed this one?".
Blur eyes, pop-eye or white spots on fins
and body, or any abnormal growth or redness on the body or fins.
These are obvious signs of already sick fish that require immediate treatment
and you should not get these fish nor any fish in the same tank. Personally
I would run far far away and not turn back until it is safe to do so.