Need Help Curing Septicemia!

[tanzen]

I have three butterfly koi that are all under a year old. When winter came around, I attempted to keep them outside, but after some pretty bad freezes and the beginning of hibernation, i brought them inside. (One koi is only four inches, another seven-eight, and the biggest ten so they are being kept in a 55 gallon until spring.) After a couple weeks of being inside, my biggest koi had developed very sudden red streaking in her tail. After a day or so of the emergence of the streaking, she developed pale ulcers also in her tail. I bought kanamycin sulfate and anti-bacteria medicated fish food. Since septicemia is supposed to be contagious, i went ahead and treated the whole tank. The kanamycin sulfate's instructions says to treat for five to seven days with a 25% water change daily and the medicated food for two weeks. I have been medicating a month with no improvement. My other two koi are just fine with no signs or symptoms of infection, illness, or general unhappiness. However, my unhealthy koi has only gotten worse. Her streaking has deepened, her ulcers have grown, her colors have faded (she looks grey), she has shredded fins from fin and tail rot, and now it seems like she is developing some sort of wounds under her scales. Her behavior is still normal though.

I do a 25% water change every night. Once a week i drain the tank down to two inches and replace the water with new clean water and purge the pump and filter with new clean water. The filter is a Laguna Pressure-Flo 1400, i unplugged the UV so it wouldn't affect the medication.

I treat the water with NovaAqua Plus water conditioner.

Water parameters:
ammonia:0
nitrite:0
nitrate:0
pH:7.6
temp:72 F

**Please take into account that this medicine has killed off all of my beneficial bacteria and i do a 25% percent water change daily and 90% water change weekly.

Tap water parameters:
ammonia:0
nitrite:0
nitrate:0
pH:6.6

Does anyone know how to help me cure my koi of this septicemia? What i've been doing obviously isn't helping.

Thank you.

*edit: A glass thermometer also broke inside the aquarium some time back. It happened when i was on vacation, so it was broken inside of the aquarium for a couple of weeks. Could the broken thermometer be the problem?

 

[mark4785]

The red streaking is usually caused by high ammonia/nitrite levels. My guess is that the ammonia/nitrite levels are increasing substantially despite doing 25% water changes. From my experience, removing 25% of the water is ineffective at lowering toxicity levels. Only the weekly, 90% water change that you say you are doing is likely to be neutralising the water toxicity.

I would personally place some zeolite within the tank to mop up the ammonia and source some filter media that is full of colonised beneficial bacteria and place this within the filter box of the tank. It might be worth adding some more beneficial bacteria using a bottled supplement named 'Tetra SafeStart'; this should increase the bacteria count enough so that it is able to manage and remove all of the potential toxins produced by the fish. A bag of 'Ultrazorb' by NtLabs is very effective at absorbing nitrites so I would also advise purchasing this and using it within the tank providing it is compatible with zeolite. Remember to remove all tonic salt before applying zeolite/ultrazorb as this will disrupt the reverse osmosis function that the bags of zeolite/ultrazorb use to draw toxins out of the water.

In order to tackle the streaks I advice applying 'WaterLife Myaxin' which specifically aims to treat streaks of the fins.

As for the ulcers, I would advise spraying/applying propolis onto them which should encourage healing. If the ulcers are getting progressively worse you should contact a fish vet who will give you advise for treating them with solutions such as malachite green which is used to kill bacteria in wounds/uclers.

 

[tanzen]

The red streaking is usually caused by high ammonia/nitrite levels. My guess is that the ammonia/nitrite levels are increasing substantially despite doing 25% water changes. From my experience, removing 25% of the water is ineffective at lowering toxicity levels. Only the weekly, 90% water change that you say you are doing is likely to be neutralising the water toxicity.

I would personally place some zeolite within the tank to mop up the ammonia and source some filter media that is full of colonised beneficial bacteria and place this within the filter box of the tank. It might be worth adding some more beneficial bacteria using a bottled supplement named 'Tetra SafeStart'; this should increase the bacteria count enough so that it is able to manage and remove all of the potential toxins produced by the fish. A bag of 'Ultrazorb' by NtLabs is very effective at absorbing nitrites so I would also advise purchasing this and using it within the tank providing it is compatible with zeolite. Remember to remove all tonic salt before applying zeolite/ultrazorb as this will disrupt the reverse osmosis function that the bags of zeolite/ultrazorb use to draw toxins out of the water.

In order to tackle the streaks I advice applying 'WaterLife Myaxin' which specifically aims to treat streaks of the fins.

As for the ulcers, I would advise spraying/applying propolis onto them which should encourage healing. If the ulcers are getting progressively worse you should contact a fish vet who will give you advise for treating them with solutions such as malachite green which is used to kill bacteria in wounds/uclers.

Thank you so much for responding.
I will try everything you suggested and see how it goes.