Common Problems
Source from Yoong's Arowana Page
This is very common problem.
All arowana keepers will run into this problem at one time. The cause(s) are often not
clear and unspecific. Proper tender loving is very important. Should any cause be
indentified, immediate action is advisable.
Possible Cause | Diagnosis | Treatment |
Poor water condition | -High amonia/nitrate/nitrite -Subnormal range temp/pH |
-Large water change. Check
filter -Adjust temp & pH to range gradually |
Stressful Environment | -Newly moved fish, recent change in
environment -Nervy, hiding, jumpy. -Darting or rapid breathing on approach |
-Cover back & sides of tank, dim
light -Add blackwater, 0.1% salt, stresscoat -Restrict traffic around the tank. -Spend time accompany your fish. |
Overfeeding | -Continues overfeeding for wks/months -Fat arowana |
Cut down feeding. |
Infection | -Parasite on body -Lifted haemorrhagic scales -Frial fins -Bulghing red anus -Abnormal swimming posture |
See Individual Topics |
Large water change mean 50% of conditioned water cahnge. Make sure all the parameters of the new water is adjusted identical to the tank water, esp temperature and pH. It is then followed by 30% water change every 2-3 days until the fish condition improved or the water quality improved.
To reduce stress of arowana, you may cut some black garbage bag into strips and put weight on one end.Make sure you wash the strips before using them. They will act like artificial plants that creat refuge area for the arowana. Remove them grdually when condition improved.
Overfeeding is often a problem. When they are over feed contineous for weeks or months, they start to loose appetite and refuse eating, the appetite will come back, just cut down the feeding.
After arowana was frighten, it is not uncommon for them to loss appetite for a while. This sometimes last for days or even weeks. It is important to identified the cause of the frightiness and delineate it. At the same time, give the fish a calm environment and tender loving care. Staying in front of the tank frequently make the fish get use to you and adapt to the environment faster. The fish will also develop a bond to you if you do it often.
This is not a disease, it is most probably
cause by change of nature to captive environement which encourage the fish to look side
and down rather then up. The 2nd most popular hypothesis is overfeeding. Genetic is the
biggest factor in this problem.
Possible Cause | Diagnosis | Treatment |
Downward and lateral gaze | -Glass, high tank woth low moving objest around it(eg kids, pets) | -Transfer to pond or cover all sides of tank |
Overfeeding | -Fat accumulating behind the eye(on dissection) | -Reduce feeding, increase excercise(eg introducing slow current, larger tank) |
Prevention is better then cure. Get a low tank. Avoid overfeeding, use floating food if possible. But most importantly do not buy the fish is you suspect dropeye.
There are other propose treatments for this problem. They included, adding ping pong ball and red flashing light into and above the tank respectively, putting a tank of cricket above the tank, pushing the eye back manually, operation, etc. I do not recommand the last three methods as they have high mortality rate.
As the name suggested, a film of white
convering form over the cornea of the eye due to various reasons. Majority of them are
mild and do not need antibiotic. However this condition must be treated seriously as its
high morbitidy and possible mortality should condition got worst.
Possible Cause | Diagnosis | Treatment |
Physical abbrasion | -Post transportation -Evident of scratch mark or other injuries |
-Water change -0.3% salt -Observe carefully |
Poor water condition | -High Ammonia/Nitrite/Nitrate/pH | -Large water change -adjust pH gradually |
Sudden water condition change | -Large water change (esp. High chlorine level) |
-Add 0.3% salt -Add water conditioner -Observe |
Infection | -Preceed by the above causes -worsening cloudiness |
-Add tetracyclin -Raise temp gradually to 32C -Add 0.3% salt |
Cloudy eyes usually take days to heal except infective cause, which might take weeks to month with or without permanant damage. Infective cause of cloudy eye without preceeding insult is uncommon. It occur only if the fish general condition is very bad. Although nutritional cause of cloudy eye is not proven in arowana, it is theoritically possible.
In this condition, the gill cover of the
arowana curl outward, initially involving only the solf part of the cover and later the
hard gill cover. If the cause is not removed, condition will get worst, gill will get
exposed, causing breathing difficulty and making the gill prone to infection. The end
result could be fetal.
Possible Cause | Diagnosis | Treatment |
Small swimming space | -Tankof size with length and
width shorter then 2.5x and 1x the length of the fish. -Fish has to "reverse" on turning |
-Move the fish to a larger tank |
Poor water condition | -Check ammonia/Nitrite/Nitrate | -Large water
change -Increase dissolved O2(add airstone) -Increase water current -message gill cover back(if fish allow) -operation(if above failed) |
When only the soft portionof the gill cover is involve and problem noticed early, conservative management might be possible. However, when the hard portion of the gill cover is involved, the condition is not reversible without surgery. Surgery is done under analgesia. The curled portion of the gill is either trimmed out or multiple pependicular(toward head) cuts is made on it.
There is a 3rd hypothesis on the cause of gill curl. Infection of the inner membrane is believed to be the cause in this hypothesis. Infection cause the inner membrane to swell and push the gill to curl outward(just like wetting the sticky side of stamp). More research is needed to prove this hypothesis.
This is a very unique syndrome affecting
more on Asian Arowanas then its Australian and South America couterpart, it is also more
common in younger arowanas. In this syndrome, the head of the fish start to get
oedematous(swollen) followed by a layer peeling off from the skin, starting from the front
of the head and moving backward.
Possible Cause | Diagnosis | Treatment |
Activated Carbon | -Sign started after introducing carbon | -Remove activated carbon. |
Activated carbon is believe to be the cause due to its close association with the syndrome. It is thought that activated carbon removed vital element in the water and hence disallow the head tissue to form normally. Other hypothesis around include irriation by the microscopic carbon particle deposite on the head. Healing is usually complete and occur withing days when carbon is removed. Zeolite product could cause similar problem too but less severe and less common. Large arowana is less sensitive Head-rot Syndrome..
This is the sudden, clean breaking of rays
of fins(esp ventral and tail) which appear like being cut. This usually occur when the
fish is under tremendous stress, eg jumping out of tank. It is believef by some a
natural mechanism for the fish to break away from the predator when caught. similar to
tail-dropping mechanism of some lizard.
Possible Cause | Diagnosis | Treatment |
Stress(eg jumping out, sudden large water parameter change) | -Cutting edge break of fin rays(often the first few of the ventral fin) | -leave it alone if gap of the break is not
visible. -cut the broken rays if gap is visible. |
Unfortunately, when this happen, the chance of the fin recovering to its original beuty is slim. Even when the breaking gap is not visible, the broken rays will atrophy and end up slightly smaller and shorter then the others. On the other hand, if the broken fin drop out spontaneously or cut out, the chance of a visible band in regenerated fin is high. In this situation, it is not uncommon that keeper choose to recut the whole fin and wish for the fin to grow back more even. But then, the outcome is again unpredictable.
It is important to provide good water condition during the recovery phase to promote healing and prevent infection. Feed the fish good balance diet, add 0.3% salt & acraflavine and do more frequent water change. Healing take months.
Unlike Tail-Drop Syndrome, the tear is
between the fin rays and run parallel to the rays.
Possible Cause | Diagnosis | Treatment |
Physical injury | -Following violent behaviour -Sign of other injury |
-Provide good food and good water -Add 0.3% salt, add acraflavine |
This is common and quite benign. They heal fast, sometime within days. X back golden is especially prone to this.
Arowana is a fish with great force, it is
not uncommon for the the fish injured by its own force while darting around. Barble is
important part of arowana as many believe it signified the horn of the dragon. Hence
it is important for arowana to have perfect barble. Regeneration of barble occur from the
base of teh barble. If this area is also injured, the damage could be permanant.
Possible Cause | Diagnosis | Treatment |
Physical injury | -Following violent behaviour -Sign of other injury |
-Observe if the distal tip completely
broken -Otherwise cut the barble at the base |
If the base of barble is not injured, full recovery can be expected. Barble can be cut near the edge and allow it to regenerate. If the base is injured or the cut barble do nto regenerate, a sterile needle puncturing the base just enough to cause bleeding can be done to stimulate growth. It is sometime good ideal to cut both barble rather then only the broken one so that they can grow out symmetrically.
It is important to provide good water condition during the recovery phase to promote healing and prevent infection. Feed the fish good balance diet, add 0.3% salt & acraflavine and do more frequent water change. Avoid small tank which will result contant rubbing of the barble onto the glass. This might result in deformed barble. Sign of regeneration can be seen in about 2 weeks time, full recovery take months.
Whole piece of scale or scales drop off
following physical injury.
Possible Cause | Diagnosis | Treatment |
Physical injury | -Following violent behaviour -Sign of other injury |
-Provide good food and good water -Add 0.3% salt, add acraflavine |
Regenerationof the scale is fast and take only days to weeks. However, it takes months for the color of the new scale to catch up with the rest. The is a chance that the scale might look different in color compare to the rest.