Everything dies except Neon Tetras?

[Chuckun]

So I've had my tank for about a year, started off with 11 neom Tetras and 5 fancy guppies (2m & 3f)

Slowly all five guppies died (5-7 days between each one), seemed like ammonia poisoning even though none was present... And the Tetras were all fine. Still are.

So then many months later (approx 2months ago) , I go and get 5 mollies, again 2 male and 3 female.. One is pregnant and dies shortly after giving birth a couple weeks in (given the stress of moving to a new tank etc, I can accept that as a risk of pregnancy..)

But now another has died, it was lying on the bottom of the tank, falling on its side, and eventually its tail was bent to the side and he seemed to be paralised down that one side... Seemed to be gasping for air too - but I assure you the water is fine, I've spent a lot of money on the best tests and everything comes up perfect as expected. And the fish have no visible problems with their gills / fins / eyes / anything.

So I think it may be an invisible disease - but its never affected the Neon Tetras, only the guppies and now seems like its going to take my mollies too...

Any ideas?

Cheers,
Jack

Edit : Tank is 160L (35gal) with Eheim Ecco Pro 300 external filter and additional carbon filters internal.

Edit 2 : I have salted the water now at 1g pure rock salt per gal but don't know if its going to help

 

[PB_Smith]

what is the water's ph?
Mollies prefer a higher ph than tetras do.
What is your maintenance regime/how often do you do water changes?


adding salt may not be the best for the tetras, the mollies will like it, but not the tetras.

 

[Chuckun]

My PH is about 7.5-7.8 and do weekly water changes alternating between 10 and 25% - the 25% one entails more vigorous cleaning, making sure gravel is free of waste etc

As for the salt, my neon Tetras have dealt well with salt in the past when trying to save the guppies previously, and I'm usinng less this time so not too worried about them

Cheers,
Jack

 

[PB_Smith]

Hmm, then I'm as baffled as you. you seem to be things right.

 

[coralbandit]

It will be considered an invisible disease.
But I think your neons are the carriers and that is why they haven't died....
There are more then a few disease that IF cured the original victim will become a hidden carrier.

 

[Chuckun]

It will be considered an invisible disease.
But I think your neons are the carriers and that is why they haven't died....
There are more then a few disease that IF cured the original victim will become a hidden carrier.

Thanks Tom, that makes sense..

Would you know any common ones off the top of your head so I can look up side effects and try figure it out? Or somewhere reliable to look?

The guppies all died with their heads floating but tails sinking, making them end up flipping upside down and freaking out, whereas the Molly simply deteriorated and struggled to move, and eventually had a curled tail and seemed to become paralysed on the one side...

 

[coralbandit]

First good link;
Bacterial infections | The Skeptical Aquarist
IMO sounds like type 1 or 2 of columnaris
Two more links;
http://www.myaquariumclub.com/columnaris-and-what-i-have-learned...-1689.html
Fish Columnaris | Fungus & Saprolegnia | Treatment & Prevention

 

[Chuckun]

First good link;
Bacterial infections | The Skeptical Aquarist
IMO sounds like type 1 or 2 of columnaris
Two more links;
http://www.myaquariumclub.com/columnaris-and-what-i-have-learned...-1689.html
Fish Columnaris | Fungus & Saprolegnia | Treatment & Prevention

Thanks again Tom - had a good read!

Although even inspecting the dead fish closely revealed no physical problems such as blemished blotches or ulcers etc at all - apart from a slight yellowy/greenish/brown discolouration on his underside, forward of the pelvic fin... Perhaps this may lead me to a more conclusive answer...

If that raises any suspicions then please don't hesitate to make suggestions

 

[Matt68005]

Hmm, then I'm as baffled as you. you seem to be things right.

Not to be rude, just something that confuses me..... just because the water quality is good does not mean that fish do not still get sick. Why do people think this? It is a bad habit people have to just say "is your water quailty good" and then act like there should never be any disease!
People that eat good exercise and do everything by the book still get cancer and other diseases.
If the OP could describe some details of the fish before they are lying on the bottom near death we could offer some advice.

 

[Matt68005]

Thanks Tom, that makes sense..

Would you know any common ones off the top of your head so I can look up side effects and try figure it out? Or somewhere reliable to look?

The guppies all died with their heads floating but tails sinking, making them end up flipping upside down and freaking out, whereas the Molly simply deteriorated and struggled to move, and eventually had a curled tail and seemed to become paralysed on the one side...

That sounds to me like the shimmies.
Coral, no offense but you think everything is columnaris.....

Overcoming the Shimmies in Tropical Fish

The symptoms of guppies drooping their tails and shimmying swimming is from environmental contiminants. You should get some activated carbon and add a healthy amount to the tank after a large water change.
Check and make sure nothing inside or out of the tank is poisining them.

 

[PB_Smith]

Not to be rude, just something that confuses me..... just because the water quality is good does not mean that fish do not still get sick. Why do people think this? It is a bad habit people have to just say "is your water quailty good" and then act like there should never be any disease!
People that eat good exercise and do everything by the book still get cancer and other diseases.
If the OP could describe some details of the fish before they are lying on the bottom near death we could offer some advice.

well for one thing as I mentioned in my post, tetras and mollies have different water preferences and if the ph or hardness were to acidic/soft that could account for the mollies death.
second where else do you propose one begin if not with questions concerning housekeeping habits and how established the tank is?

how did you surmise that I think that disease shouldn't happen if water quality is good?
all I said was that "I am baffled", not that there shouldn't be anything wrong because the water is good. My being "baffled" is more because I am not as well versed in freshwater maladies as I am with salt water, therefore any further advice I could offer would be merely guessing, hence my reply "I am baffled"

does that ease your confusion?

 

[PB_Smith]

Not to be rude, just something that confuses me..... .

from the link you provided;

The classic scenario is when mollies are kept in soft or acidic water conditions. Though tolerant fish in many ways, they do not do well in soft or acidic water, and it is very common to see mollies kept that way start to shimmy. To varying degrees, almost all the other livebearers sold to hobbyists are sensitive to soft or acidic water conditions, and consequently the shimmies may be seen among any of them kept in the wrong water conditions.

and you wonder why I asked about PH and water conditions....

 

[Matt68005]

You have a point. But it is from water that has contimanints, not water that is too soft or acidic.
Most mollies and guppies grown commercially in the U.S are grown in florida....soft acidic water.
Guppies and mollies are kept throughout the world in soft acidic water conditions, and do just fine for most people. The only problem would be if they are grown in a hard water environment and suddenly put into very soft water at home.
Again, sorry for my rudeness. You should definately make sure the person is keeping the fish in proper water. Its just that all to often i see a post made about sick fish and nobody offers medication that could save the tank. They instead ramble on about water quality this water quality that. Fish have to get use to YOUR water, it is not considered worthwile to adjust the GH and PH in a tank with chemicals, because it causes greater fluxations during water changes, or if you miss dose.
I dont believe that this person's water GH or acidic is the problem, i do think it is some sort of poisin chemical contiminant, or even expired meds or water de-clorinator.

 

[coralbandit]

That sounds to me like the shimmies.
Coral, no offense but you think everything is columnaris.....

Overcoming the Shimmies in Tropical Fish

The symptoms of guppies drooping their tails and shimmying swimming is from environmental contiminants. You should get some activated carbon and add a healthy amount to the tank after a large water change.
Check and make sure nothing inside or out of the tank is poisining them.

Certain bacterial and protozoan diseases, such as finrot, mouth fungus, and slime disease, seem to be associated with the shimmies as well
^^This from your link in this post^!!!
You know shimmies are a symptom like dropsy not a real disease??
Usaully bacterial.....
Kind of thought fin rot,mouth fungus were also known as columnaris?
Maybe I need to learn?
So you think water changes and regular maintenance will solve OPs problem?

You have a point. But it is from water that has contimanints, not water that is too soft or acidic.

I dont believe that this person's water GH or acidic is the problem, i do think it is some sort of poisin chemical contiminant, or even expired meds or water de-clorinator.

Soooo you believe the neons are resistant to this poison also huh???

 

[PB_Smith]

You have a point. But it is from water that has contimanints, not water that is too soft or acidic.
Most mollies and guppies grown commercially in the U.S are grown in florida....soft acidic water.
Guppies and mollies are kept throughout the world in soft acidic water conditions, and do just fine for most people. The only problem would be if they are grown in a hard water environment and suddenly put into very soft water at home.

Sounds more like your assumptions rather than fact.
The very article you provided states that they DO NOT do "just fine" in soft/acidic water and in 40 years I have found that to be the case. Actually if memory serves the healthiest mollies I can recall were actually in brackish water and we even kept some in salt water tanks.

Fish have to get use to YOUR water, it is not considered worthwile to adjust the GH and PH in a tank with chemicals, because it causes greater fluxations during water changes, or if you miss dose.
I dont believe that this person's water GH or acidic is the problem, i do think it is some sort of poisin chemical contiminant, or even expired meds or water de-clorinator.

Again you are incorrect I'm afraid. some fish can adapt to local water conditions, but many can not and the water needs to be conditioned/treated in order to accommodate them, whether it be making it soft/acidic for discus, rams and tetras or making it hard and high ph for African cichlids.
People go to great lengths and expense to adjust their water parameters to suit their chosen species, so I am at a loss where you get the notion that it isn't worthwhile.

Sure lots of fish do "just fine" in less than optimum conditions, but wouldn't you rather that the fish thrive?

IMO the "community tank" is a bad mish-mash of species often having very different requirements and consequently some of them are not going to thrive.
The most enjoyment and success will be had if we tailor the system to a specific type of water quality/habitat and then stock with only fish whose natural habitats we can best duplicate.

IE: all south American tank or an all Asian tank, etc.

 

[Chuckun]

Relax guys!
We all have different opinions and that's why I came to a forum, I'm open to all suggestions so I can at very least eliminate them until I find the right cause I appreciate all your comments !

They seem to be getting back on track after feeding them lots of watercress - thought it was worth a try, and could be coincidence...

I've also invested in a high end UV steriliser which I'm going to set up tomorrow in case it is something bacterial.

I'll update in a week or so with a status report

 

[Chuckun]

OK so down goes another Mollie.. Again, the only thing wrong to look at her was that she has a slight greeny/yellow smear behind one of her gills.. And mouth wide open this time..

Tetras are starting to get a little fin rot too.. Looks more like they're being nipped but if anything they are the ones that try to nip the Mollies..

I also appear to have had a massive ammonia and nitrite spike despite daily water changes and a huge 50% change just last night...

 

[Chuckun]

Does anyone think this could purely be down to general hardness? That's the only thing I see wrong consistently, I hear mollies need a really high GH where as mine is relatively low...

 

[Matt68005]

I think it could, but i am still convinced its not the main cause.
Could you get an antibiotic?
If you want to raise your GH you can use limestone rocks in your tanks.
How low is it?
Like i said before, fish get used to whatever water they are born in.
You can look for a substrate that will raise Hardness.

 

[PB_Smith]

have you checked to see what the water they are being kept in at the lfs is like?
that would be a good starting point. if there is a big difference then it's a safe guess that could be the cause. if not you know to look elsewhere.
scientific method-process of elimination