Five Ways Your Fish Can Get a Koi Bacterial Infection and How to Treat It

 koi bacterial ulcer

Although they are quite beautiful and hardy Koi are prone to bacterial infection.

This occurs most often when they come in contact with  Aeromonas or Pseudomonas bacteria. These naturally occurring bacteria are found mainly in the water of ponds and lakes. They do not exist in tap water because of the chlorine it contains.

However, if you fill your pond or water garden with tap water you will discover that the bacteria can eventually be found in this water too. Once the chlorine evaporates Aeromonas and Pseudomonas are quick to move in. Unfortunately they then have the ability to cause Koi bacterial infection.

The good thing about these bacteria is that they don’t cause much harm when found in low quantities in a clean and healthy pond.

Also, the outer coating or epidermis of the fish protects them from infection. However, harmful bacteria can infect your Koi when its epidermal layer is broken because then the bacteria can penetrate it’s outer cover.

Not only does it harm the fish already present in water, but can spread very rapidly too.

Commonly, when the Koi’s dermis layer is exposed to bacteria, infection can start to spread rather rapidly. This process takes place when flukes use their haptens, resembling small fishhooks, to attach themselves, thus attracting harmful bacteria onto the surface of the fish.

Another thing that can break the Koi’s slime coat is a puncture or scratch from a sharp object, such as a rock, that exposes it to bacteria.

The Koi can also be exposed to bacteria due to poor water quality or stress caused through overcrowding or moving the fish from one pond to another.

So how can these infections be treated? If you are interested in trying some home remedies you can follow the  procedures below.

Koi bacterial infection can be present in wounds either smaller or larger in size. Therefore separate procedures are followed to treat them.

When treating small sores use a paper towel to dry off the wound. Next, soak the sore in a solution of hydrogen peroxide on a cotton swab for 30 seconds before you place the Koi back in the water. You need to repeat this procedure for 3 consecutive days.

The treatment  for larger sores is similar. The only difference being, after following the same procedure and drying off the wound again, you need to apply a Debride Medicated Treatment on the sores. This procedure also needs to be followed for 3 consecutive days.

However, if this treatment doesn’t work effectively, you may need to seek the advice of your veterinarian. You can  also feed medicated food to help heal your fish faster. This method may not always work, especially in fish very small in size.

This advice is for informational purposes and is not intended to replace proper medical treatment by a licensed veterinarian when treating stubborn or severe cases of Koi bacterial infection.


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