Dead Neon Tetra

[nigel bentley]

First of all, Happy New Year guys.
This is my first post for a good while and im a bit flumaxed tbh.
About 3 weels ago, i purchased 12 neon tetras for a lightly stocked 90l tank and one by one they have died.
Tank details are:
90l Capacity
Co 2 No
Filter Eheim 2213
Water parameters:
Ammonia 0
Nitrite 0
Nitrate 20ppm
Ph 8(normally is around 8)
Water temp 22 deg
PLants Anubias
I feed every other day.
Since adding the neons, i have lost a dwarf gourami also.It leaves me with 2 albino corys who seem fine.
The neons had were displaying lack of colour and were hanging around the bottom.
I have heard of neon tetra disease and wondering if anyone else has encountered this?
My main question is this: I want to shut down my 90l and concentrate on my 400l.
I'm a little unsure whether to add my albinos to the 400l.
Any thoughts would be grarefully received

 

[Bradders]

First of all, Happy New Year guys.
My main question is this: I want to shut down my 90l and concentrate on my 400l.
I'm a little unsure whether to add my albinos to the 400l.
Any thoughts would be grarefully received

Happy New Year. I'm sorry to hear about the issues.
If it were me, I would wait 2-3 weeks and observe the albinos - sort of a quarantine. If there are no issues with the fish after that, you have more confidence that they are healthy for transfer.

About 3 weels ago, i purchased 12 neon tetras for a lightly stocked 90l tank and one by one they have died.

Despite what the Internet tells you, Neon Tetras are not hardy fish that cope with all conditions. They can quickly succumb to disease, and that disease can spread rapidly. It would be good to see a shot of your aquarium and also any description of the fish when they died, including time of day and any notable/visible illnesses. The more information the better.

 

[nigel bentley]

Hi Bradders, thanks for your super fast response
The fish seem to die during the night, and were displaying lack of colour and hanging around bottom of tank.
I havent cleaned the filter for around 4 months but flow is still very good. I dont think this is the cause as fish were fine until i added neons. The few plants ive got are not in the best shape, i add api leaf zone once a week. Again, im not sure is this has contributed.
Been keeping fish many years now and a similar thing did happen before with blue neon tetras.
It seems to me they either have a disease or im thinking that as it has happened before maybe its the hard London water?
Black neon tetras seem a little bit more hardy.
Please see photo

 

[nigel bentley]

Thanks for the quick reply Bradders, please see attached photos.
The NT seem to die more during the night and seem less vibrant in colour.
i do 25% water change fortnightly. I have not touched the filter in around 4 months. Not ideal, just been so busy. Having said this, the flow is still great and tank is lightly stocked.
I noticed some baby ramhorn snails at back of tank, so maybe i have overfed?
Maybe im being hard on myself and the NT were ill when i got them.
Similar thing happened to me about 20 years ago, again with NT.
Incidentally, in my 400l tank, o have a shoal of Black Neons and they do seem much hardier

 

[Bradders]

The fish seem to die during the night, and were displaying lack of colour and hanging around bottom of tank.

Fish died overnight, so I would look at how much dissolved oxygen you have in your aquarium. You have low plant mass, so you rely (almost entirely) on surface agitation (or bubblers to create) that gas exchange. If there are no physical illness signs on the external of the fish, then this would be my first area to investigate due to the overnight issue. (Everything takes oxygen when the lights are off - including fish, algae and plants, with bacteria being a constant). Bear in mind low oxygen is a stressor, so discolouration and lethargy would occur.

i do 25% water change fortnightly. I have not touched the filter in around 4 months. Not ideal, just been so busy. Having said this, the flow is still great and tank is lightly stocked.

With blackwater fish, I recommend a 50% once a week. They just like near-perfect water conditions to maximise the chances of health. If it were me, each week I would take out 25% of the water, give the entire tank a good clean, then take out the last 25% to remove the gunk suspended in the water column from cleaning. Then replace it with water-conditioned water.

Incidentally, in my 400l tank, o have a shoal of Black Neons and they do seem much hardier

I always lean towards the environment. I was discussing the other day that my Cardinal Tetra's are happily living in water conditions (high pH, high TDS, hard water) that should be a recipe for disaster. But the tank has 40-50% plant mass, is well over-filtered and has plenty of gas exchange. Maybe there is something you are doing in the 400L which is different to the smaller?

Maybe im being hard on myself and the NT were ill when i got them.

When you care (which you do!) you are always hard on yourself! But dont let that put you off. Have a think about the environment and see if anything could be amiss. Of course, it could have been a bacterial infection that spread - but its always good to sit back and take stock of the environment.

 

[mort]

Is the thermometer accurate? It might be the angle but it looks like it's under 20c which could make the neons more susceptible to disease. It doesn't look like neon tetra disease to me from the corpse.

Neons should be fine in rock hard water but it does definitely shorten their lifespan. You would be lucky to get more than a couple of years out of them while in softer water they can easily live 3-4.

 

[Bradders]

Neons should be fine in rock hard water but it does definitely shorten their lifespan. You would be lucky to get more than a couple of years out of them while in softer water they can easily live 3-4.

Hi Mort - do you have any studies on this aspect? I am very interested in understanding the effects of hard water on fish health but the Internet has not been kind in helping me find data!

 

[nigel bentley]

Hi Braders, i think you have hit the nail on the head here. This tank is in our bedroom and although there is surface agitation, its low, to keep the noise level down.Adding the neons compounded any oxygen level issues

Mort, as you say, the corpse doesnt indicate disease. Plus, i went into the shop where i purchased the fish and the neons looked fine there.
I dont believe temp is an issue, just checked temp is 22 deg (probably my photography lol)

Been keeping fish 35 years and im gutted ive done this now.Didnt cross my mind about oxygen as i did have a little agitation.

Moving forward, i have added a few more corys, added an air stone. I will monitor for a few weeks and rehome to my 400l if all okay. Going to shut down small tank(wife is chuffed) and just keep the 400l.

Thanks so much for your help Bradders and Mort for working this througj with me

 

[Bradders]

Thanks so much for your help Bradders and Mort for working this througj with me

Absolute pleasure. Isn't UKAPS a really, really great place for us all?! Happy New Year, Nigel.

 

[nigel bentley]

Correct mate,this is a fantastic group. Have a great New Year

 

[mort]

Hi Mort - do you have any studies on this aspect? I am very interested in understanding the effects of hard water on fish health but the Internet has not been kind in helping me find data!

Hi Bradders, I don't have anything but anecdotal experience but believe it's a quite widely held view. I live in an area with very hard water and have kept the same fish in tap and mostly rainwater. I only got breeding behaviour in soft water and I believe alot of tetra species only breed in soft water or need soft water for the larva to develop.
I've always believed it was due to chronic stress from being in an environment where they weren't designed to be and the associated osmotic stress. These natural environments are normally high in tannins and these can be antibacterial whereas in harder water bacteria thrive and there are different pathogens. With osmotic regulation it just puts a constant low level stress on them that doesn't affect their behaviour but uses resources and makes them more susceptible to bacteria and pathogens, especially ones they wouldn't naturally encounter .
I think it's also been shown that there can be a build up of deposits in their kidneys which can cause a whole host of problems including organ failure. I don't know if kidney failure, osmotic stress or unnatural bacterial load, are more likely to cause issues or if something else is playing a role but it's why I prefer to keep fish which like the water I can provide.


Hi Nigel, hopefully things are sorted now then but it's a surprise that you lost a gourami if it was oxygen related as they can breathe atmospheric oxygen, as can the cories, dwarf gourami are quite weak fish though.

 

[Connswater]

Hi Bradders, thanks for your super fast response
The fish seem to die during the night, and were displaying lack of colour and hanging around bottom of tank.
I havent cleaned the filter for around 4 months but flow is still very good. I dont think this is the cause as fish were fine until i added neons. The few plants ive got are not in the best shape, i add api leaf zone once a week. Again, im not sure is this has contributed.
Been keeping fish many years now and a similar thing did happen before with blue neon tetras.
It seems to me they either have a disease or im thinking that as it has happened before maybe its the hard London water?
Black neon tetras seem a little bit more hardy.
Please see photo

I have successfully kept neons in hardwater 18 KH, much the same GH, at 24-26 degrees centigrade, for small fish, they can live for many years, certainly five years is possible. Sadly Neon Tetra disease cannot be cured but a UV will prevent it spreading. Loss of body colour, particularly under the dorsal fin and or towards the adipose fin, is often a sign. The disease will kill other similar body shaped characin tetras and I think it will also kill many rasboras. Catfish seem immune. Sorry to hear of your problems, but if, as you say, the stock in the shop are 100% fine it is unlikely to be disease, but, and it is a big but, many shops run a UV on the centralised filtration system and you only need one diseased fish to cause havoc when operating without UV. They may have lost a diseased fish or two and not even noticed.