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You find in these pages, all you need to know about keeping seahorses in captivity and breeding babies

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© photo 24 Seahorses convalescing


Seahorses may be affected by a disease through negligence, stress, or aggression. They are more fragile and more difficult to cure than fish, this is why you must act quickly and eliminate the real cause.

The following disturbances, from less important to very important show an unbalance in the immune system and/or the environment :
  • behavioral change;
  • rubbing against objects and/or attempt to get rid of parasites and/or bacteria with the tail;
  • long stays under air diffusers and/or inside the pump or filter streams;
  • dull or dark color compared to a normal tint;
  • overproduction of mucus;
  • light superficial stains, especially in the area of the small horns, loss of skin;
  • eyes and/or body covered with a cutaneous veil;
  • torn flukes, even rot;
  • light stains, loss of skin of the male pouch;
  • more or less severe loss of tail skin, or even complete stripping;
  • blood stains with or without loss of skin;
  • loss of weight (internal parasites);
  • nodules (with loss of skin);
  • swollen belly; bubbles under the skin and/or on the tail = gaseous embolism;
  • unusual way of swimming, acute nervousness or persisting upside down swimming;
  • rotten eggs (with brown liquid) swollen belly;
  • fungal infection on the body;
  • difficulty in eating; eventually no feeding at all;
  • difficult breathing, ventilation;
  • motionless stay at the bottom, staring eyes;
  • floating at the surface = gaseous embolism;
  • complete swelling of the head, eyes, body, with eyes opacity.
An advice: if ever your arm is itching after you have put it into the aquarium, it may mean that the tank is infected. Watch your animals carefully.

© photo 65 young dead seahorse
young dead seahorse

Diagnosis and treatment

For a seahorse lover the most difficult thing to know in order to establish a precise diagnosis is what sort of pathogenic organism he/she is dealing with. You often have to treat without knowing. In spite of existing books giving a good idea of what diseases may take place in sea water, and even if you can spot enemy number one by empiric methods, and watch through a microscope - naturally less powerful then a professional one - you will find that the spotted enemy looks at the same time like nothing and everything. Moreover some identical symptoms may be provoked by totally different micro organisms. In most cases, unicellular cilia or flagellate parasites are the cause. Bacteria often act as agents of a secondary infection. However, bacteria may sometimes be the only aggressor. As far as viruses and worms are concerned, though less frequent, they usually provoke incurable diseases at the present state of medical knowledge (the old seahorses often die of virus disease).

When dealing with a fish tank, using drugs meant for human beings as proposed by some books, has to be carefully managed. Seahorses do not react as other fish. If the proposed drug and its quantity determination are supposed to be harmless for fragile fish and invertebrates, one can say that seahorses will accept the treatment. It is better to renew the treatment several times than to face an intoxication. Contrary to this rule, copper solutions are well accepted if the ill animal is not too weakened. Distrust as well several drug solutions found in specialized shops. Always use first the weakest prescribed dosage - if mentioned - or reduce yourself the dosage. Proscribe the use of combined drugs, they may interact of react in an unpredictable way, as manufacturers often sell them without indications of composition. No doubt the best thing to do is to use bread spectrum treatments against bacteria or parasites and make a good cleaning of the tank.

In presence of parasitical infections or sometimes bacterial, depending on their state, you may put seahorses in fresh water for 2 to 10 minutes per day. This is to be considered as a strong local anti-parasites treatment. A too ill animal will not bear such a treatment and will soon fall in a comatose lethargy. It is then better to refrain from doing so and try to treat the tank as a whole. This method is in principle not enough to heal, but may help, especially when the cause of the disease has been found and that other treatments given in parallel have proven to be efficient. Do not renew fresh water immersion unless it is clear that the animal has not suffered from the previous treatment. Otherwise you would meet an opposite result to the expected one and the disease may be aggravated. Whatever long the immersion time, stop it as soon as you witness abnormal signs. A seahorse staying motionless at the bottom but breathing normally and following your movements with its eyes is not necessarily in danger. In case of doubt, touch it gently with the fingers, it should start swimming. I PERSONALLY AVOID USING THE FRESH WATER IMMERSION BECAUSE SEAHORSES SUFFER TWO IMPORTANT CHOCKS : ONCE WHEN PUT IN FRESH WATER, SECOND WHEN PUT AGAIN IN THE TANK.

In presence of gaseous embolism (bubbles on the body, on the tail or swollen pouch of the male) it can be caused by several factors such as gaseous imbalance or other fish tank parameters, parasitic or bacterial infection. In such a case you must eliminate the reason (test your tank) and treat it with appropriate anti-parasitic/bacterial product as said above. If a male seahorse has a bloated pouch and floats to the surface (head down swimming, except when it wears youngs), it has air. Massage 2 to 3 days the pouch delicately from bottom to top to force it to open the pouch to release the air, failing which it will not feed anymore and die.

The best and surest method is to prevent and not to treat. It does not pay to act as a "Sorcerer's apprentice".

NB: A big belly does not necessarily mean disease. It happens that some seahorses which are generally greedy, have an overweight problem. As for human beings this is not a short or middle term issue. Trouble may appear on the long term in their life span (heart problems). A diet will be of no help as the animal may be stressed and would start over eating again on the first occasion. Let it live its own life the way it wants. On the other hand it is most important to give from the start an adequate food quantity.

Sometimes when born, a seahorse may show a physical or motion handicap. This is not to be considered as a disease and will not affect other animals. Once again let nature lead the game. If the handicap is really too important the seahorse dies quickly, otherwise it will develop the necessary aptitudes to survive.

The vibrio is an invisible bacteria which can at a glimpse colonize an aquarium and very quickly decimate a population of seahorses. The sources of infection are numerous :
  • sick corals ;
  • infected live food ;
  • living stones, algae and infected plants in poor health ;
  • badly maintained and kept aquarium ;
  • or simply introduced by contaminated animals (may sometimes be in good health though carrying the vibrio).
The vibrios feed upon sediments and polluting elements. It is thus necessary to maintain a clean and healthy aquarium, with quality water, without any pollution and to respect the rules of frequent cleanings. Above all it is also necessary to find the cause of the infection and to eliminate it.

It is important to know that the vibrio can hide for a long time and increase within favourable ground and explode at one go when its population is stong enough to lead a striking attack.

If your seahorses die in a inexplicable way, while all the parameters of your aquarium are good, think about the vibrio.

There is a test in the fish shop to detect this devastating infection.

One of the effective ways of treating vibrio is to lower gradually the water temperature to stop the infection and then slowly raise it again. This can apply besides also to the other diseases. You can also equip the tank of an UV-sterilizer and use punctually a scum device.

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* English translation with the help of my friend Romain

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