Black growth on neon tetra

[BCGirl]

I'm looking for any insight people may have. One of my neon tetras developed a black type growth on his side. I've been monitoring it and it slowly seemed to be growing over months, so quite slow. None of my other tetras got it and he swims and eats and generally seems in good health but it is obviously something and was spreading. I am limited with meds in Canada. Melafix, Pimafix and aquarium salt didn't seem to do much. Seachem Paraguard seemed to reduce it's size a bit but nothing seems to have got rid of it and I worry it will continue to spread. My next attempt will be Jungle Fungus Clear which I managed to get my hands on. I did treatments spaced out over time I haven't been inundating the poor guy with meds after meds but I'm at a loss and would like him healthy so I can move him in my community tank and keep the rest of my fish safe and healthy. Hard to get a pic but this is the best I can do. Tank is fully cycled, no water issues and heated. Any insight is greatly appreciated.

[Colu]

 little information would be helpful what are your water parameters ammonia and nitirte etc have you added anything new to the tank around the time the fish developed symptoms

[BCGirl]

@Colu Of course. It is an established tank Ammonia 0 Nitrites 0 Nitrates 5, temp 76 20% water changes weekly (netrites poop a lot). Tetras (6) have been in there for about 9 months. Started out as a smallish spot and grew gradually. Nothing new was added, except maybe one plant from a reputable store and the timing didn't coincide with growth of the spot. All other tetras are fine. I did add two more tetras at one point and didn't quarantine them (idiot) and they brought ick but I was able to treat it and all survived and the spot was in existence at the time. I think it stressed him obviously as he did get a bit of a fungus on his lip after the ick but the paragaurd got rid of that right away. All that is left is the blackish growth.

[Colu]

Possible bacterial as it has been going on for a Couple of months I think that would have killed him by now  it's a difficult one I think jungal fungas clear fizz tabs are your best option as they treat fungal and bacterial infections just thinking outside of the box possible heater burn that would explain the permanent discoloration and why you have not seen much improvement @BCGirl

Edited February 23, 2022 by Colu

[BCGirl]

Thanks @Colu. It is a hard one and I am glad it hasn't killed him. I'm one tablet into the Jungle Fungus treatment and will do a second dose tomorrow. Sure hope it improves.