Fish disease and sickness -

Both wild caught and farm raised fishes carry parasites/bacteria which usually does not cause significant harm in normal water conditions. This is the same as us humans carrying millions of bacteria and dust mites on our hair and skin, without serious effects. However, these 'harmless passengers' can cause serious trouble, when the following or combinations of the following factors occur:

1. Fish is under stress, causing a lowering of immune system.
2. Poor water conditions, especially sudden changes in water conditions or parameters.
3. Physical injuries such as cuts, scratches or bites

If left untreated, a single infected fish will pass the infection to all other tank mates. Over time, your tank becomes a death trap killing everything in it.

(common aquarium sickness treatment)

Prevention -

Most of the time, parasites/disease are introduced to the tank by new additions to the tank. The majority of these problem additions will be fish or plants, while the rest will be aquarium decorations which have been in infected water. To be safe, always boil non-living objects which may have been in contact with parasites and diseases before you add them to your aquarium. This is especially true for pieces of rocks or wood which you have picked up from a natural setting. Obviously, we cannot boil fishes before we add them to our aquarium, therefore:

1. Avoid aquiring fish which exhibits the following symptoms :-

* abnormal swimming pattern (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 in tandem with other fishes in its tank.

* signs of injuries to fins and body. e.g. bleeding, ulcers, skin or fin tear
Skin/fin tear are usually caused by tettorial 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.

* not eating.
A healthy fish will devour any food gladly. 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 is highly possible that it is sick.

* eyes blurry. Popeye or cloudy eyes, or white spots on fins and body.
Fishes which display these symptoms are already sick. Do not introduce them to your tank. Treatment for these sickness is available below.

2. In your home aquarium pay attention to your fishes for at least a few minutes a day. Stressed fishes may exhibit certain unusual behaviour :-

* not eating as usual.
* always hiding behind shelters or water plants, being bullied by other tank mates regularly.
* coming up to the surface to breath regularly, could be a sign of an over-crowded tank or insufficient dissolved oxygen in the water. (in the latter, changing fresh water will help)
* gasping for air at the water surface, never swimming down.
When this happens to every fish in the tank, you need more aeration in your water. If you are not using an air pump but only a filter, adjust the deployment height or the height of the water outlet so that there is more surface agitation, causing more air to dissolve into the water.
If this sympton is happening to only one fish in the tank, watch closely at the eyes for cloudy eyes. Most fishes gasp for air at the surface when they are turning blind. It may be because they are less likely to bump into submerged decorations and plants. Also, it is partly due to them being sick and is finding more difficulty breathing.

3. Ensure the water condition is kept to the ideal level.
*Check for presence of ammonia and variation in pH at least once a month.
*Change the water regularly, making sure that the temperature and pH level is similar.
*It is best never to change more than 50% of the water at one time.
*Avoid cleaning your biological filter all at once. If there are several filter components, alternate cleaning each component. Also, it is best not to clean your biological filter under the tap due to chlorine which can kill off all beneficial bacteria. It is advisable to syphone water from your tank into a pail, and to use that water to clean your filters.

Treatment -
The following are common diseases that happen to freshwater aquarium fish.

1. White Spots (Ich)
2. Fin Rot
3. Fungus
4. Cloudy Eyes
5. HITH (Hole In The Head)
6. Blackening Fins and Body