Is this neon tetra disease?


Hi all, I’m very alarmed. I’ve just checked the fish inn my husbands tank, a 200L Juwel Lido. One angelfish pair that lay eggs every 2 weeks, four rams, 10 neon tetras, 5 cloud minnows, a bristlenose and three corys. Some pond and ramshorn snails.

pH 7, ammonia and nitrite 0, nitrate 5ppm. Temp 26.

Planted aquarium. Baby dwarf tears, blyxa, pygmy grass, anubis, Amazon sword, Xmas tree moss, seiyru rock and a piece of drift wood. Aquarium soil over volcanic rock (not sure of brands), and thin layer of gravel over soil because the cichlids keep digging everything up and the soil goes everywhere.

Everyone in there has been happy since set up. We have c02 on a timer and the led light is on a a timer too. 6 hours a day only. We have carbon in the juwel filter that we replace every 4-6 weeks even though I don’t think we really need it, but my husband likes it. We replace the top filter floss weekly, the water is changed weekly, around 30%.

The most recent fish addition was a large fully grown blue eyed lemon male bristle nose around two mths ago now I think? He died on the weekend. We didn’t see any warnings signs that he was unwell. Our remaining bristle nose is a common brown and seems fine at this stage.

Tonight I checked the fish because I noticed our black female angelfish had a white lower lip. Then I noticed a neon tetra that looks like his scales are coming off and he is discolored and his fins look like they’re rotting and then I noticed others, some with clear cysts on their mouths some with white growths on their mouths and some with dorsal fins looking like theyre deteriorating.

Is this the dreaded ntd? What do I do? Will they recover? Do I euthanase affected fish?
And if every fish dies or has to be euthanased, is this aquarium permanently infected? Strip it down, bleach and start again? Omg ‍♀️

Totally gutted right now. I know there’s other things this could be but I feel ntd is what we have


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The tetra on the first and second picture has Dermocystidium and what looks like a secondary infection with finrot symptoms.
The other one has a columnaris-like bacterial infection.
The Angelfish might have contracted the same, but it looks more like an injury, maybe from intraspecies aggression.

But definitely no signs of NTD. That disease is quite rare and looks different. But whenever people google diseases on neon tetras they get that search result and expect the worst.

What you can do immediately: Not panic and do high volume waterchanges. And treatments of the diseases. You will need a hospital tank for this, as treating in the main tank would need all fish to withstand at least 3 different meds in a row, which is going to nuke the biological balance of your tank as well. With the diagnosis you can look up fitting meds available in your country. Make sure to use specific meds against the diagnosed conditions and not broad band meds.

What you can do longterm: Change the stocking and optimize holding conditions. Half your stock needs rather cold water (neon tetras ~23-24°C, white clouds: room temp) which makes them succeptable to disease and parasites, the other half (angels and rams) needs high temperatures. 26°C is a rather bad compromise. It also explains why the neons have those specific diseases. (Well except the Dermocystidium, which is a whole other can of worms).

You will have to decide which species to keep and when stocking up make sure they are compatible in water parameters and temperature. Also, find out what your GH and KH is, as most of your fish are softwater species.

About Dermocystidium: The good news - it's not lethal. The bad news - there is no specific treatment. Fish can live years with it. It has been shown, though, that optimal conditions are very helpful in keeping it at bay.

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