It's all @Paul B's fault... my journey to an immune reef (hopefully!)

[MnFish1]

I think this is a rumored answer (I couldn't think of a better word) We really don't know if young fish in the sea die of disease as they get eaten so fast and it is really hard to study that. Those scientists sitting around in a lab in Cooz Bay Oregon don't do a lot of research in the ocean as they can't afford it and probably can't swim because they went to school on Tibet.
baby fish get their immunity from their Mother. (I posted that someplace here and I didn't make it up, but I probably would have if I couldn't read it) Their Mother was immune as all fish in the sea have to be.
If the Mother fish was in a quarantined tank for a long period of time and she has not been exposed to parasites, the babies will also have no immunity. For all the people who don't believe that, they should not read anything I post because that is the premise which I run my tank with and the reason my fish will never get sick.

See all these baby fish? I took this recently in (put a place here because I forgot where it was--------------------) Look at the 37th fish from the right about in the middle. Yes, even that fish, the one with the greenish blue eyes is immune from almost everything. I say almost because at this time probably all of them were eaten by something a little larger. If their Mother was quarantined, and not exposed to parasites, those fish would not be alive not would anything else in the sea. This is my point.

You may even notice some "Normal" hair algae to the right, but that is for another thread, A thread where people think they can "cure" it and feel it is a disease or curse from the Moon Goddess.

If all 'wild fish are immune' why is it that (per another one of those pesky scientific articles): I bolded the last sentence because they were looking for symptomatic fish in the article - not just doing random biopsies.

Out of a total of 211 fish (15 species), 143 (67.7 %) were found to be infected with the mean intensity of 7.67 parasites per field of view (x4 magnification). The prevalence of C. irritans in fish caught during the spring (91.0 3% on average) was significantly higher than that of the fish caught during the summer (39.29 %). A wide variation in the prevalence of the parasite was shown among the fish species. The highest prevalence and intensity of the infection occurred in Plataxteira, Diodon holocanthus, Paracanthurus hepatusat 100 % of infection and density of 12 parasites/field of view (x4 magnification) while and the lowest prevalence of C. irritans appeared on Rhinecanthus aculeatus, Zancluscornutus, and Zebrasoma veliferum with less than 50% of fish infected. Clinical signs of fish infected of C. irritans showed such as tiny white spots on skin, gills, and fins; ragged fins, changes in skin colour, cloudy eyes and increase mucus production.

 

[Paul B]

There are parasites on all fish, immune or not. There are parasites on my fish because I want them to have parasites just like they do in the sea. Those parasites are not killing or even annoying the fish. They are just there for the ride and the fishes slime is there to make sure the parasites don't enter the fishes body. Parasites eat slime. Even us Humans are full of parasites, but they do not bother us and we don't even know we have them.
The fish with the cloudy eyes, raggedy fins etc, I don't know what was the problem with those fish but I have also seen quite a few fish like that in the sea. That happens when fish are either attacked and hurt or are old. Fish are constantly in a battle to stay alive and everything is trying to eat them, including me. They get bitten and because of that they slow down. Most fish get bitten many times, Other fish are not really stupid so they pick on them and eventually they die.
But fish that do not get bitten, bullied or have their identity stolen do not get sick in the sea. (or in my tank) It just doesn't happen and if you see one of those scientists, you can tell him I said that.

Let me say something about scientific articles and all articles in general. I have been submitting articles to magazines for decades and every time I have done that, without fail, they were published as fact. I could have been on LSD that I got by raiding a funeral home or home depot and drank a fifth of gin, then written the article, and they still published it as fact. My credentials are basically that I am a bald electrician with absolutely no degrees in anything and they still published everything I ever wrote as fact. So don't believe everything you read from scientists, George Washington, Lady GaGa or any one else.
I have no idea if those scientists even spent any time in the sea or if they read it in an article, maybe even one I wrote.

Many people today tell me about that Russian Roulette thing, I went out with a Russian girl for about a year and my fish still didn't die. It's not Russian Roulette to keep your fish healthy, it's Russian Roulette to keep parasites away from your fish.
OK, take a little time out and go to the disease forum to look for tank crashes after they were quarantined.

I linked what those scientists wrote, if you want to believe it or not. parasites eat slime and can stay alive and healthy in a tank eating slime forever, not 72 days, but forever. Burgess came out with that 72 day thing and I remember when he came up with that, I think it was in the 70s. I disagreed with him them as I disagree with him now.
Just like Dr. (I forget his name but he is the same age as me, begins with an S) came out with DSBs and how great they are. I still disagree with him.
This hobby is full of this stuff and always has been. I have seen all these theories come and go. Now we have carbon fines cause HLLE. I say NO it doesn't.
You can agree with everything scientists or researchers write, if you did we would all think the Earth is flat or the universe is never ending. I think that at the end of the universe is a brick wall with tar paper on top of it and beyond that are Strawberry fields forever.
OK, I will stop now before I get on a roll.

 

[brwaldbaum]

Can Paul or someone else help me understand what's been said so far? Admittedly, I'm not the brightest person, but I think I am reading contradictory statements.

1) Fish in the wild--who are immune--are often found parasitized (sometimes heavily), but, because they are immune, the parasites don't bother them.

2) Paul necropsies every one of his deceased fish and never finds a gill parasite--because they're immune. (Note: As far as I know, it is no longer believed that parasites "abandon ship" soon after a fish's death.)

 

[Gareth elliott]

There are parasites on all fish, immune or not. There are parasites on my fish because I want them to have parasites just like they do in the sea. Those parasites are not killing or even annoying the fish. They are just there for the ride and the fishes slime is there to make sure the parasites don't enter the fishes body. Parasites eat slime. Even us Humans are full of parasites, but they do not bother us and we don't even know we have them.
The fish with the cloudy eyes, raggedy fins etc, I don't know what was the problem with those fish but I have also seen quite a few fish like that in the sea. That happens when fish are either attacked and hurt or are old. Fish are constantly in a battle to stay alive and everything is trying to eat them, including me. They get bitten and because of that they slow down. Most fish get bitten many times, Other fish are not really stupid so they pick on them and eventually they die.
But fish that do not get bitten, bullied or have their identity stolen do not get sick in the sea. (or in my tank) It just doesn't happen and if you see one of those scientists, you can tell him I said that.

Let me say something about scientific articles and all articles in general. I have been submitting articles to magazines for decades and every time I have done that, without fail, they were published as fact. I could have been on LSD that I got by raiding a funeral home or home depot and drank a fifth of gin, then written the article, and they still published it as fact. My credentials are basically that I am a bald electrician with absolutely no degrees in anything and they still published everything I ever wrote as fact. So don't believe everything you read from scientists, George Washington, Lady GaGa or any one else.
I have no idea if those scientists even spent any time in the sea or if they read it in an article, maybe even one I wrote.

Many people today tell me about that Russian Roulette thing, I went out with a Russian girl for about a year and my fish still didn't die. It's not Russian Roulette to keep your fish healthy, it's Russian Roulette to keep parasites away from your fish.
OK, take a little time out and go to the disease forum to look for tank crashes after they were quarantined.

I linked what those scientists wrote, if you want to believe it or not. parasites eat slime and can stay alive and healthy in a tank eating slime forever, not 72 days, but forever. Burgess came out with that 72 day thing and I remember when he came up with that, I think it was in the 70s. I disagreed with him them as I disagree with him now.
Just like Dr. (I forget his name but he is the same age as me, begins with an S) came out with DSBs and how great they are. I still disagree with him.
This hobby is full of this stuff and always has been. I have seen all these theories come and go. Now we have carbon fines cause HLLE. I say NO it doesn't.
You can agree with everything scientists or researchers write, if you did we would all think the Earth is flat or the universe is never ending. I think that at the end of the universe is a brick wall with tar paper on top of it and beyond that are Strawberry fields forever.
OK, I will stop now before I get on a roll.

Fish for the most part also mass produce spawn. This is true for a lot of creatures from sea turtles to insects. By producing large quantities of offspring it guaranties some will themselves spawn. Outliving predators and disease. But also that the most fit genes are the ones past down.
Disease on any population will effect some greater than others; even ebola only has a 80-90% mortality rate with only palliative care available. Statistically i find it hard to believe that a large number of fish are not lost to disease in the wild. Just witness the parents of substrate spawning cichlids, eggs infected get eaten to save those that are not.

Yes the marine fish have evolved around the parasite, and resistance might be common.

But the parasites themselves evolve, because a fish is resistant to parasite 1a does not mean survival to parasite 1b. Perhaps 1b evolved a new anchoring mechanism or now produces antigen c which the immune system reads as “ignore me”.

I am not disagreeing that your system works for you, just stating replicating a natural environment does not equal every fish will survive every disease.

Also necropsy of visual physiology also dismisses another cause of death by parasite. The creation of an entry point for smaller pathogens. Without microscopic analysis of tissue samples would anyone ever fully know that a fish died of a bacteria that entered via the attachment point of 1 mite?

 

[Paul B]

1) Fish in the wild--who are immune--are often found parasitized (sometimes heavily), but, because they are immune, the parasites don't bother them.

Whats not to understand? The parasites on a fishes skin don't do anything, they are eating slime. The fish has scales to protect them from most things. Parasites kill the fish when they cover the gills. It's not the little bit of blood the parasite gets, it's the fact that there are so many parasites on the gills that the gill can't exchange oxygen and the parasites, just by hanging on there rip the gills to shreds.
All fish in the sea have parasites at one time or another as there are so many parasites. If fish were not immune, there would be no fish, just fat parasites. Parasites are not trying to kill the fish, just get lunch as parasites don't go to deli's for a pastrami on rye.
The fishes immune system keeps the parasites from invading the gills because fish exude slime and in that slime (If the fish is healthy and immune) are antiparasitic, anti bacterial and anti viral substances that protect the fish just as we have mucus in our trachea and nasal passages. We can, and do have bacteria, viruses, and parasites on our skin but if they can't get in, they don't bother us.

The problem comes if we quarantine and then keep the fish away from pathogens. In time, which differs in different fish species, the fish loses it's immunity to those things because antibodies to those things cost the fish a lot in calories to keep them up. Fish slime is constantly produced because it is water soluble so it washes off and it is sticky like honey which is also water soluble. The slime washes off along with the parasites.

This is fine as long as the fish never encounter those things. But if they do, they have no defense. That 72 day thing is also ridiculous because now we know that parasites could live in a tank forever just by sampling fish slime. That is the reason for all the threads that start out by saying:
I let my tank go fallow for 72 days, then after I put the fish back, it crashed. It's an old wives tale that I heard from an old wife and some researchers in the 60 and 70.
Immune fish have no problem with parasites and they keep the fish healthy, the more parasites in the water, the stronger the immunity. Many people can't see the logic in that because they have been brainwashed for so long. I used to be in that group, but I advanced past it just as modern medicine now is using our immunity to try to keep us healthy.

People in areas where malaria mosquitoes bite them constantly don't all die from malaria. I know because I was there, but I was not immune because I wasn't born there so I had to take antimalaria pills every day.

(Note: As far as I know, it is no longer believed that parasites "abandon ship" soon after a fish's death.)

I don't know where you got this and I am not even sure if it's true. But I autopsy fish as soon as I can, sometimes the fish is still living and I euthanize it. Parasites are easily seen on a gill even without a microscope, but I have one.
It doesn't matter, immune fish are not affected by parasites as my tank proves. In 3 years my tank will be fifty. If in fifty years my tank full of parasites never crashed, is that more evidence than some scientist in a lab studying a parasite for a few months who probably doesn't even keep fish?

 

[brwaldbaum]

Whats not to understand?

1) Immune fish in the ocean are parasitized.
2) Immune fish in your tank have no parasites under the microscope, even though you say your fish have parasites but are unaffected by them.

Paul, I believe you when you say your fish are healthy and problem free. I believe you 100%. But the reasons you give for your success sound less like evidence-based assessment and more like religious conviction. Please don't take that personally. I'm glad you and people like you are in the hobby.

(I'll try to find the reference for parasites not abandoning their host when I get home from work.)

 

[MnFish1]

There are parasites on my fish because I want them to have parasites just like they do in the sea. Those parasites are not killing or even annoying the fish. They are just there for the ride and the fishes slime is there to make sure the parasites don't enter the fishes body. Parasites eat slime. Even us Humans are full of parasites, but they do not bother us and we don't even know we have them.

It is simply not true - and there are pictures of skin biopsies - to prove that cryptocaryon DO NOT only eat 'slime': trophonts revolve continuously within the host’s outer body tissue layer or epithelium. They feed upon body fluids, tissue debris and whole cells of the fish (Colorni & Burgess, 1997). Once the skin is damaged, infection can occur . It is true that humans have commensal organisms that live on/in themselves - but there are many parasites that kill people world-wide - including malaria - and not only people that 'are not from that area'.

I linked what those scientists wrote, if you want to believe it or not. parasites eat slime and can stay alive and healthy in a tank eating slime forever, not 72 days, but forever. Burgess came out with that 72 day thing and I remember when he came up with that, I think it was in the 70s. I disagreed with him them as I disagree with him now.

If there are no fish in tank, what 'slime' are they eating. There are theories and there are facts. The fact is that with no fish in the tank, cryptokaryon will die off after a time.

People in areas where malaria mosquitoes bite them constantly don't all die from malaria. I know because I was there, but I was not immune because I wasn't born there so I had to take antimalaria pills every day.

The reason you needed to take medication for malaria in Vietnam is that in order for you to get 'immune' to it, you would have to get 'sick' from it - and the risk of getting sick is far higher than taking the pills. In any case, the immunity is only 'partial'. But it is still a serious disease.Nearly half of the world's population is at risk of malaria. In 2015, there were roughly 212 million malaria cases and an estimated 429 000 malaria deaths. Increased prevention and control measures have led to a 29% reduction in malaria mortality rates globally since 2010. Sub-Saharan Africa continues to carry a disproportionately high share of the global malaria burden. In 2015, the region was home to 90% of malaria cases and 92% of malaria deaths.

It doesn't matter, immune fish are not affected by parasites as my tank proves. In 3 years my tank will be fifty. If in fifty years my tank full of parasites never crashed, is that more evidence than some scientist in a lab studying a parasite for a few months who probably doesn't even keep fish?

There are many reasons your tank may have been less effected by cryptocaryon - that have nothing to with your reasoning (its your reasoning that people are questioning, not that fact that fish can be immune to Cryptocaryon):

1. Your fish may be immune (they have to be - if they don't have the parasite right)? Its well known that fish can become immune to ci. (or the CI in your tank has 'died off)
2. The concentration of fish in your tank may not be enough to maintain active disease?
3. Since you don't add fish that often, they are not exposed to new sources of infection.
4. The sterilization methods you use have decreased the number of infectious particles to a level that your fish can handle.
5. A combination of the above.
6. Some other reason.

However, you have not 'proven' that 1, your tank is full of parasites. To do that you would have to add non-immune fish and determine their mortality. Or you could show it microscopically. Also - I wish you would stop using general words like 'parasites' - and 'quarantine' without being specific as to which parasites and methods you're talking about. Even the word 'immune' is so general it makes it impossible to discuss things rationally.

For example - in places where they are trying to develop vaccines to CI, mortality after vaccination depended on the dose of the parasite in the water. Even though all the fish had the same vaccine and antibody, etc levels (i.e. they were immune) when x trophonts were added/liter of water mortality was say 4 percent. Where x times 5 trophonts were added the mortality was 40% when 10x the number of trophonts were added mortality was 80%. Thus its impossible for you to merely say 'my fish are immune'.

 

[MnFish1]

Let me say something about scientific articles and all articles in general. I have been submitting articles to magazines for decades and every time I have done that, without fail, they were published as fact.

There is a difference between an 'article' submitted as an 'opinion' and a scientific article submitted in a peer-reviewed journal. In the second case, experts in the field review the manuscript, perhaps suggest changes or perhaps reject the article entirely. There certainly seems to be a spirited debate in this thread as to whether all of the opinions are 'facts'.

So - you have an 'immune tank' (meaning to me that your fish are 'immune' to cryptocaryon. Lets say you took 10 black mollies which had not been exposed to CI and added them to your tank? Would they somehow be instantly immune as well? Lets say you add 10 tank raised clown-fish, would they all survive the multitude of parasites (velvet, ich, etc) you claim to have in your tank? If they did survive, its not because they were 'immune' but because they hadn't been exposed to those parasites. It would mean that the level of parasites you claim to have is not as high as you think. The same logic applies to any 'new' fish added to your tank that has not been exposed to 'your methods'. There is innate resistance to disease that is non-specific - i.e. slime, cytokines, etc) - but immunity to specific pathogens is not immediate

 

[Gweeds1980]

Whilst I totally love the debate here, just a reminder that this thread was for me to share my journey and the obstacles/ outcomes of it...

I don't share Paul's views / evidence on parasites not affecting the fish in my tank, evidenced in this thread by my heniochus coming down with velvet. What I do find interesting and would like to understand more is why he survived with no treatment whatsoever and why no other fish had ANY symptoms.

 

[Brew12]

Whilst I totally love the debate here, just a reminder that this thread was for me to share my journey and the obstacles/ outcomes of it...

I don't share Paul's views / evidence on parasites not affecting the fish in my tank, evidenced in this thread by my heniochus coming down with velvet. What I do find interesting and would like to understand more is why he survived with no treatment whatsoever and why no other fish had ANY symptoms.

I'm going to go with your Amyloodinium Ocellatum either being very picky eaters and only like the flavor of the heniochus or that your other fish just aren't ripe yet and need to age in the sun a little longer.

 

[MnFish1]

Whilst I totally love the debate here, just a reminder that this thread was for me to share my journey and the obstacles/ outcomes of it...

I don't share Paul's views / evidence on parasites not affecting the fish in my tank, evidenced in this thread by my heniochus coming down with velvet. What I do find interesting and would like to understand more is why he survived with no treatment whatsoever and why no other fish had ANY symptoms.

He and the other fish were in good condition. He had a mild case or was partially immune, not every fish dies of velvet. There was a low concentration of parasites in the water and the other fish likewise were not as affected. The fish you had were partially immune to velvet from prior exposure. Maybe it was a variant of CI and not velvet. Light, temperature effects. Maybe you were lucky.

As you know - parasites 'job' is not to kill the host - if they killed all the hosts, they would be committing suicide (because most parasites are host specific). So a great many animals survive/live with parasitic infections. Often it leads to chronic illness in the animal. Which is why scientists don't usually recommend 'adding parasites' to an environment - but rather protecting the hosts from the parasites.

 

[Paul B]

Paul, I believe you when you say your fish are healthy and problem free. I believe you 100%. But the reasons you give for your success sound less like evidence-based assessment and more like religious conviction. Please don't take that personally. I'm glad you and people like you are in the hobby.

I also love this "discussion" as do my fish. The fish in my tank after autopsy have no parasites on their gills because there are different antibodies for the gills as the slime there has to be very thin to allow oxygen exchange. I lined that someplace. I never said my fish don't have parasites on their skin.
For the rest of this. As you know, I am in the process of moving and am packing so I will get back to this. I just love to debate MnFish

 

[Greenstreet.1]

Keep it up guys I’m loving all the info.

 

[atoll]

Keep it up guys I’m loving all the info.

Well in many ways this thread goes round in circles and each side is never going to convince the other as to exactly why our fish (those of us whose fish don't tend to get sick) do so well, live long lives and spawn but we never QT and furthermore don't even believe in it. On the other side are those who meticulously QT and have few problems with disease. However, some that try Paul's methods may fail for whatever reason (I suspect due to the possibility they have cut too many corners). Even those who have followed the QT code to the letter also sometimes fail and their fish get sick and may die.
We can argue till the cows come home about they whys and the what fors. One thing is for certain there are a number of us old guys who practice similar ways to Paul (I have been keeping my tanks in a similar to Paul and so have a number of my friends here in the UK for over 25 years and our fish don't show signs of itch or any other disease). Both sides have stated their cases and are entrenched in what they believe is the right way. I will just add and say" I firmly believe you can't improve on nature, she has had millions of years to perfect her ways, I try to follow her lead as much as I am and think is reasonably possible".
Those who deny our methods are often the type who are unable to think outside the box and follow those who speak in an eloquent and have a greater command of the language. They sound very convincing and most will probably have an ology or more so you can understand why many will lean towards their ways. My children have ologies but can't do many of the things I can and they marvel at my skills, maybe there is a clue there. You listen, question then decide like you pays your money and takes your pick. I made my decision and won't be changing my ways anytime soon but no doubt you won't be surprised by that at all.

 

[Greenstreet.1]

All has it’s pros and cons. What works for some may not work for all.

And just for the record I’m not against anyone I’m on this reef to learn and to learn how to properly take care of my reef and all that’s in it.

 

[Paul B]

It is simply not true - and there are pictures of skin biopsies - to prove that cryptocaryon DO NOT only eat 'slime': trophonts revolve continuously within the host’s outer body tissue layer or epithelium. They feed upon body fluids, tissue debris and whole cells of the fish (Colorni & Burgess, 1997). Once the skin is damaged, infection can occur . It is true that humans have commensal organisms that live on/in themselves - but there are many parasites that kill people world-wide - including malaria

Of course they don't eat only slime. Who said that? I said they can live on slime because the fish has immunity to them so they don't get to the fishes skin. They only get to the skin on quarantined fish that have no immunity. I also said, I disagreed with Burgess in the 60s and I still do.
Healthy Humans can live with malaria as they become immune. Malaria is a problem in mostly depressed countries where the people are in bad shape. The people I fought in Nam were bitten constantly as I was, but they seemed mighty healthy to me. But the people in the poor villages eating nothing but rice were dying from the disease. I took pills.

If there are no fish in tank, what 'slime' are they eating. There are theories and there are facts. The fact is that with no fish in the tank, cryptokaryon will die off after a time.

They are not eating slime in the empty tank, they are eating slime on the quarantined fish in that other tank.

The fact is that with no fish in the tank, cryptokaryon will die off after a time.

That was also Burgess and I don't agree with his 72 day thing. It will probably die after a time, but what time is that? That was in a sterile lab, not a tank like we run or the sea. That study was also over 50 years ago.

Sub-Saharan Africa continues to carry a disproportionately high share of the global malaria burden. In 2015, the region was home to 90% of malaria cases and 92% of malaria deaths.

That is true, have you seen the way sub saharan people live and what they live on. Why don't they all die from the disease? It's because the people eating correctly with clean water become immune.
All fish will die from parasites if they are not immune as many of the posts here prove. As is said many times, my tank and a few others are Russian Roulette.

There are many reasons your tank may have been less effected by cryptocaryon - that have nothing to with your reasoning (its your reasoning that people are questioning, not that fact that fish can be immune to Cryptocaryon)

Not "Less effected" Zero effected.
Your not calling me a Nut Job are you?

1. Your fish may be immune (they have to be - if they don't have the parasite right)?

Wrong, my fish are immune because they do have the parasite. It just won't hurt them.

 

[Gareth elliott]

Sub-saharan survival rates to malaria are also effected by a genetic trait. Those afflicted with sickle cell anemia are naturally less affected by the parasite. Its theorized thats why this genetic disease has continued in the gene pool. The afflicted person living long enough to pass on their genes where they are less likely without it.

That being said malaria has a disproportionately mortality amongst children children regardless of diet. The death rate reduction in half over the last 20 years is from mosquito nets not immunity.

 

[Paul B]

My computer crashed there for a minute. I think it had ich

2. The concentration of fish in your tank may not be enough to maintain active disease?
3. Since you don't add fish that often, they are not exposed to new sources of infection.
4. The sterilization methods you use have decreased the number of infectious particles to a level that your fish can handle.
5. A combination of the above.
6. Some other reason.

There are about 20 fish in my 100 gallon, long tank and the thing is filled with rock. That should be enough fish to maintain ich or any other disease. Tanks get infected with one fish in it. That just doesn't make sense to me. It's like when people say my fish are not delicate enough so they don't get ich. Like Really!
This year I added 2 cardinals, 2 Janss pipefish and an anthias. Yesterday I went to He-- with myself and added a soft coral. Next week I will hopefully add mud and a few thousand amphipods and water. If I had a bag of ich I would add that but they don't sell it on Amazon.

The sterilization method I use? You mean my Ozonizer? Like I said, if that is the answer, EVERYONE GO OUT AND BUY AN OZONIZER, THAT IS THE SECRET

I am going with #6, some other reason. I will say Luck
I love this guy. He is supposed to be that color so he doesn't have the heartbreak of psoriasis

 

[Paul B]

Also necropsy of visual physiology also dismisses another cause of death by parasite. The creation of an entry point for smaller pathogens. Without microscopic analysis of tissue samples would anyone ever fully know that a fish died of a bacteria that entered via the attachment point of 1 mite?

Gareth. Thank you for posting and I had to think about that, just a little. If a clownfish dies after it is 20 or 30 years old, would we be concerned?
If a pipefish died after 5 years would that bother you? Would you look for cause of death even though those fish lived to their presumed lifespan.
My Mother died at the age of 99 with no seeming cause of death. They asked me If I wanted an autopsy performed. I said, Are you kidding, she was 99. Who cares what she died from, I will call it old age no matter what the official cause of death was.
It's the same with fish. Immune fish, and my fish die of old age. I "think" it is old age because there are a few references of a few fish as to how long they seem to be able to live. Bangai Cardinals surprisingly have a lifespan in the sea of 3 or 4 years. I almost didn't believe that when I referenced it. My pair died about 5 years old. If I didn't know their lifespan I would have went crazy looking at the cause of death. Should I have autopsied them to find the cause of death? (I did) Weather they died from parasites, gout, swim bladder disease, dropsy, or mononucleosis, who cares. They have to die of something as they are not eternal beings like groupies or snowflakes.
If our fish live to their presumed lifespan, why would we care what they died from? At old age they will possibly get covered in parasites, stop eating or crash into the glass because thats what happens to fish when they get old, just as that is what happens to people when they get old, except for that glass thing. When fish stop eating at the end of their life, they lose their immunity and ability to swim.

Of course if your clownfish dies at 17 years old, he probably died from a disease and you should find out why because immune fish "almost" always only die of old age or an accident like a 1967 Oldsmobile Cutlass convertible with dual exhausts and baby moon hub caps runs into your tank. Fish rarely, if ever get heart attacks or strokes. Maybe they do but I have never seen that. Fish, (in the sea) unlike us eat what they are supposed to eat. Live, whole fish and it is not deep fried or covered in tartar sauce. They also exercise constantly and don't watch much TV. They don't eat potato chips or drink soda. (or as you southerners call it "pop".

So to sum it all up. If All your fish always die at or near the end of their presumed lifespan, don't worry about it. Go out to dinner and have a nice glass of Pino Noir.
If that is the case, and they have Pino Nior, your fish are fine and this thread is silly.
If on the other hand, any of your fish ever die way before their presumed lifespan, you are doing something wrong and it is your fault. Not the fish, the wholesaler or Trunp. They died of disease that you allowed them to get by not feeding them correctly or allowing them to lose their immunity. Just my opinion of course.

References:
Me

 

[brwaldbaum]

1) Immune fish in the ocean are parasitized.
2) Immune fish in your tank have no parasites under the microscope, even though you say your fish have parasites but are unaffected by them.

Paul, I believe you when you say your fish are healthy and problem free. I believe you 100%. But the reasons you give for your success sound less like evidence-based assessment and more like religious conviction. Please don't take that personally. I'm glad you and people like you are in the hobby.

(I'll try to find the reference for parasites not abandoning their host when I get home from work.)

Here's one of the references:

https://www.cambridge.org/core/jour...n-dead-hosts/11859FC3EDEAB121CB41C81DAB98AF84