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Black ghost knife fish with possible nitrate poisoning.


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Hello everyone of aquarium co-op! Just wanted to say I'm a big fan and appreciate all of the youtube videos! Ive come here with a bit of a problem. My black ghost knifefish is sick! It looks like a bacterial infection going by the white patches on his gills and I'm treating it with a combo of melafix and kanamycin according to their instructions. But his behavior seems to insinuate something other than a bacterial infection.

His behaves as though he's drunk for lack of a better description plus today he isn't eating, and every so often he comes to the top and gulps air which tells me it could be nitrate poisoning which I've read that they die really quick after nitrate poisoning and he has been this way for a couple weeks now. If it is nitrate poisoning I think methylene blue will help but I won't assume anything. It is also noteworthy to mention that this happened very shortly after I added some cory cats to his tank as a clean up crew which could mean he got pricked by their spines and aren't catfish poisonous?


What I've done so far to try and help:

I've attached a dimmer to his aquarium light to reduce his stress a bit

I've added 2 brand new air stones to help his breathing as well as I put a small circulation pump at the top to break the waters surface to aid gas exchange In the water 

My water test results:

Ph - 7.6

Kh - 4 (about 60ppm)

Gh - 17 (about 340ppm)

Ammonia- 0.25

Nitrite- 0

Nitrates - 40ppm - 80ppm




Edited by Brolyfanatic777
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Whatever it is, my first course of action to anything water parameters related would be anywhere from 50% to 80% repeated water changes because if your tests are off and it does happen to be nitrite, or ammonia they function as blood toxins binding to the hemoglobin and turning it into methemoglobin which cannot transport oxygen to the cells. Repeated water changes will work quicker than methylene blue if you really suspect it might be nitrate cycle related unless you know there's a problem with your tap water to begin with.

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That's exactly what I was saying, but if you don't trust the tests and have any reason to think your parameters are off in regards to nitrite, or ammonia then always do a few large water changes first before you start adding anything else to the water. If you suspect infection then a whole different approach is warranted.

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Ok, I've done a 15 gallon water change he is in a 40 gallon grow out tank. Tomorrow morning I'll be doing another 15 gallon water change which should get all of the melafix and kanamycin out of the water as well as the carbon I've put in. I've got one more question, could he be constipated? As a knife fish I've assumed that all he needs are pellets and meaty things. Maybe I've been feeding him wrong. God I'm so embarrassed he is such a special fish I want him to be well! In my research I've found that things like insects with their exoskeleton or canned vegetables can help him relieve himself, or an Epsom salt dip? I feel like I could do all the research in the world but it means nothing without the prior experience! Lol never thought I'd get so attached to a fish!

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