Deadly Fast Spreading Fungus...Please Help!!

[Silencedogood]

Hi all-
I have a 30 gallon main tank and a 10 gallon nursery tank. Last week I had a couple of guppies that were big enough to add into my main tank. Within two days, two of my guppies that I had added died and my four neon tetras as well. Their symptoms were melting tails and fins to nothing and then a secondary fungus infection that quickly spread over their bodies and coated their bodies with a thick cream-colored fungus. I treated my main tank with API Fungus Treatment and everyone else was fine. I had previously added four new fish from my LFS and thought that was probably the reason. Yesterday I decided to add some of my bigger guppies from my 10 gallon to my 30 gallon. Within a FEW HOURS that I had added had melted tails and fins and one of them had developed the secondary fungal infection. None of the guppies had any symptoms of any illness before I added them to my main tank. I put the infected guppies back into my 10 gallon and am currently treating with the API Fungus Treatment. I was wondering if anyone has had any experience with this type of fungus or knows how to handle it. I breed my livebearers and sell them to my LFS so I would like to get this figured out. Thanks in advance.

 

[FallenPepper]

Lots of heat to disinfect and salt

 

[JuiceBox52]

I had this fungus. Super fast and deadly. I used jungle fungus clear. I first noticed it on one and q tanked it. It spread really fast and I list nearly all of my fish. Do lots of really large water changes

 

[Colin_T]

Pictures of the fish so we can confirm it has fungus?

What is the ammonia, nitrite, nitrate, pH and GH of the tank water?

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Fungus does not spread that rapidly. The most likely scenario is a bacterial infection that damaged the body and allowed fungus (assuming there was any) to get in.

Poor water quality can cause fins to rot away and the fish produce mucous that looks like a cream/ white film over their body and fins.

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All new fish should be quarantined for a month before being added to a display tank to prevent new diseases getting into the main tanks.

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The best thing to do if livebearers get sick, is a huge (75%) water change and completely gravel clean the substrate. Clean the filter too. Then add a heap of salt (4 heaped tablespoons per 20 litres of tank water). Keep the salt levels high for 2-4 weeks and then water change it out.

 

[Silencedogood]

The best thing to do if livebearers get sick, is a huge (75%) water change and completely gravel clean the substrate. Clean the filter too. Then add a heap of salt (4 heaped tablespoons per 20 litres of tank water). Keep the salt levels high for 2-4 weeks and then water change it out.

I had previously done 75% water changes in my tank but my LFS told me NOT to do such large water changes because in New York our water is typically on the softer side and it is not good for the fish. Also, the last time i did such a large water change, my fish went into shock. Not really too sure about 75% but what about 50%?

I can't get any pictures of the fish because my lights in the 10 gallon are failing so it's pretty dark.

I haven't tested the water parameters; the treatment that I'm doing has made my water green; would that affect the results of the parameters?
I had one guppy die this morning. This is an exact replay of last week. Also, the guppies have no symptoms until I add them to my main tank but all of my fish in the main tank are fine.

 

[Silencedogood]

Temp in my tank is 82F.

 

[Byron]

I had previously done 75% water changes in my tank but my LFS told me NOT to do such large water changes because in New York our water is typically on the softer side and it is not good for the fish. Also, the last time i did such a large water change, my fish went into shock. Not really too sure about 75% but what about 50%?

Colin will deal with the actual issue, but I can respond to this related issue. And the first thing is, that in New York City you have soft or very soft water. This will weaken fish like guppies which absolutely must have moderately hard or harder water. And a basic pH (I suspect the pH is below 7 with your soft water). This is undoubtedly behind the "fungus," but Colin can deal with that. I don't know what other fish you have or intend, but livebearers will not last long or be healthy while they do manage to survive, in soft water.

As for water changes, the above issue is a problem obviously. But leaving that aside, provided the parameters (meaning GH, pH and temperature) between the tank water and the tap water are reasonably close, there is absolutely no harm in massive water changes. A regular weekly WC of 50-70% is advisable for any aquarium, again with the parameter caveat. With you soft water,if you stay with fish requiring soft water, you will have no issues with water changes. And the fish will be less likely tohave other problems. Inappropriate parameters (GH especially, but also pH) seriously weakens fish.

 

[Silencedogood]

Colin will deal with the actual issue, but I can respond to this related issue. And the first thing is, that in New York City you have soft or very soft water. This will weaken fish like guppies which absolutely must have moderately hard or harder water. And a basic pH (I suspect the pH is below 7 with your soft water). This is undoubtedly behind the "fungus," but Colin can deal with that. I don't know what other fish you have or intend, but livebearers will not last long or be healthy while they do manage to survive, in soft water.

As for water changes, the above issue is a problem obviously. But leaving that aside, provided the parameters (meaning GH, pH and temperature) between the tank water and the tap water are reasonably close, there is absolutely no harm in massive water changes. A regular weekly WC of 50-70% is advisable for any aquarium, again with the parameter caveat. With you soft water,if you stay with fish requiring soft water, you will have no issues with water changes. And the fish will be less likely tohave other problems. Inappropriate parameters (GH especially, but also pH) seriously weakens fish.

I have swordtails, mollies, and guppies. My livebearers are typically always healthy (I add baking soda and Seachem Alkaline Buffer for the ph, gh, and kh). This also affected my neon tetras; it killed all of them. My tank ph is always 7.2 or above.

 

[Byron]

I have swordtails, mollies, and guppies. My livebearers are typically always healthy (I add baking soda and Seachem Alkaline Buffer for the ph, gh, and kh). This also affected my neon tetras; it killed all of them. My tank ph is always 7.2 or above.

Unless I am mistaken, none of these is going to increase the GH and that is the most important factor. Alkaline Buffer deals with pH, as does baking soda. This is fromm Seachem:

Alkaline Buffer™ is a non–phosphate buffer to raise pH and alkalinity (KH) and buffer with Acid Buffer™. These buffers are designed for the planted aquarium or for very hard water where phosphate buffers may pose an algae or cloudiness problem. Alkaline Buffer™ raises pH and buffers between 7.2 and 8.5. It is gentle, safe, and enhances the freshwater environment.​

You should not use this with any other buffering agent (like baking soda) as the two will cause more stress for the fish. So from what I see here, GH is apparently soft or very soft (what is the actual GH?) which is harming the livebearers long-term because they must have calcium and magnesium dissolved in the water which they take in via osmosis and then use the minerals internally to carry out normal essential physiological functions. They just cannot do this in soft water, so while they are now surviving they are not thriving and at some point this will become significant enough to be noticed. For up to months it will not be obvious to us, but it is doing its damage to the fish. I can assure you biologically that the livebearers are not healthy, if the GH is below around 12 dGH.

Baking soda is a dangerous substance and should not be used because it adds sodium and it is not a permanent buffer.

Guppies are so weakened generally these days due to generations of inbreeding that they frequently have difficulty sooner. But it is a matter of time. Neon Tetra also suffer from the same inbreeding which is why they frequently succumb to issues that other fish would be able to handle or fight off. I have no idea if the issue is really fungus, but again Colin can work that out, though he will need a photo.

 

[Silencedogood]

@Byron Thanks for the advice.
my gh is typically around 200ppm. Sorry I wasn't clear; I use either baking soda or alkaline buffer. I really was wondering why they broke out in this fungus or whatever it is as soon as I added them to my main tank.

 

[Byron]

@Byron Thanks for the advice.
my gh is typically around 200ppm. Sorry I wasn't clear; I use either baking soda or alkaline buffer. I really was wondering why they broke out in this fungus or whatever it is as soon as I added them to my main tank.

OK, this has eliminated a likely suspect. But how do you achieve 200 ppm GH? And I do still suggest not using baking soda, the Seachem will work better, though I personally would not go down this road. When I had to provide a tank for livebearers and rift lake cichlids (not together!) I used a calcareous substrate so I did not have to add any chemicals, and it last for decades.

 

[Silencedogood]

I'm not sure; I typically add around 1 teaspoon of baking soda after every water change and that takes care of it. I will consider a calcareous substrate though. That seems easier than adding something to the water ever water change.

 

[Silencedogood]

I do have a ton of pest snails in my tank and there are always empty shells in the gravel. Could that raise gh levels?

They still have the fungus though. Does anyone have any ideas?

 

[Byron]

I'm not sure; I typically add around 1 teaspoon of baking soda after every water change and that takes care of it. I will consider a calcareous substrate though. That seems easier than adding something to the water ever water change.

Baking soda willnot increase GH, only KH. You should get to the bottom of why the GH is 200 ppm, if it is (maybe this is actually KH?). What is the GH of your source (tap) water on its own?

I do have a ton of pest snails in my tank and there are always empty shells in the gravel. Could that raise gh levels?

No. Empty snail shells means the snails are either not geetting enough food to sustain them, or there is something in the water poisoning them, or some fish is managing to eat them, or the GH is not sufficient to supply calcium for their exoskeletons. Remember, GH is the dissolved calcium and magnesium and this is what makes water soft to hard, and it is the critical parameter for fish and some snails.

 

[Silencedogood]

What is the GH of your source (tap) water on its own?

My tap water is 7 dGH