fin rot

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Aug 25, 2004
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my white mollie has the disease fin rot and its tail its like really rotting and is looks really bad im getting something for it on saturday. if i managed to cure it would the tail stay the same as it is or will my fish just die? plz help
p.s im always asking questions lol sorry :rolleyes:
Fin rot
Fishes' fins turn whitish and die back. Fin rot often follows damage or injury. It can also be caused by poor water quality.
Remedy: First, fix the water and remove any fin-nipping fish. Change some water (25% is good) and add 1 tsp/gallon salt to promote healing. If bad water quality or an aggressive tankmate was the problem, that should be adequate. Healing will begin within a couple of days.

If it worsens, decide first whether it's fungal or bacterial. Fungal finrot looks like clumps of cotton on the fins and usually follows injury. It is commonly seen in African cichlids or fish that have injured themselves against decorations. Bacterial finrot is whitish, but not cottony (unless it's columnaris), and can be contagious. The fish then need to be removed from the tank and medicated.

Fungus: For fish large enough to handle, catch the fish, and dab malachite green directly on the fungus with a Q-tip. This is extremely effective. Repeat treatments may be necessary.

For small fish, a commercial fungicide such as Maroxy may work. For severe infestations, try a bath in methylene blue (enough so you can barely see the fish) until the fungus turns blue or for 20 min. If you add methylene blue directly to a tank, you will kill plants and trash your biological filter.

Bacterial: Antibiotic treatment in a quarantine tank. This is stressful for the fish, and doesn't always work, so be sure of what you are doing before you attempt it. If the fish is still eating, the best bet is an antibiotic food. Tetra makes one that works well -- just buy the one for bacterial diseases and follow the directions on the can.

If the fish is not eating, a bath treatment is necessary. A combination of Kaynamycin and Furanace usually works, especially for Columnaris. Again, treat in a separate tank and aerate heavily
To get the best result with fin rot it's always best to treat as soon as you see even the slightest problem. So don't delay until saturday when friday would give the fish a better chance. I have seen fin rot eat a tail down to the bone in about 3 days :(
If you can treat the fish on its own that would be better. As well as the fungus treatment you can add aquarium salt and melafix to the water. Both will help speed up the process of healing. (but don't add salt if you have any type of catfish/scaleless fish in your tank it will burn and possibly kill them!! :( )
If the rot is down to the tail bed then there is no hope sadly, the fish will die eventually and I think to humanly kill it would be kinder as they can go on for days like that :-( . But If you have tail tissue and all bones still intact with the right treatment the fish will recover in time and the tail should heal. :thumbs:
we was going to get some treatment today this morning but when i woke up the fish was dead with no tail at all but i am going gettin some cure for the tank anyway coz the disease spreads doesnt it?
Finrot/fungus rot is due to a weakened immune system brought on by stress. Stress can be caused by either change of accomadation (ie movement from one tank to another) bullying fin nipping from another fish or poor water conditions.
The fungus that causes the infection is always in the water and only affects the fish when the immune system becomes compromised.
If all your other fish are well and showing no other symptoms then you should be fine. But look closely at all the fins on the fish, it start with a small errosion at the edgse of the fine, often with a fluffys wite edge to it (that's the fungus) This is the time to treat the fish to give it its best chance of a full and quick recovery. So do get some treatments in just in case you have any future outbreaks. :thumbs:
Another good treatment to have in is one that deals with bacterial problems. Often fish go off their food and die without no outward symptoms, this is due to a bacterial infection of some kind. It can also cause ulcers and sores onthe fishes body too. :crazy:
Hope this helps :)

N x

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