TO suggest that you know how to ensure immunity (using only nutrition) is my problem with your argument.
You have to hear the entire thing. Nutrition is but one fact and it is important but nutrition alone will not make anything immune. That is where most people fail when they are trying to get their fish in great health and immune. Immunity is inherent in all fish in the sea, if it were not they would succumb to diseases every time they ate because their food is loaded with parasites and infectious agents. All we have to do is to help the fish keep that immunity. Quarantining does the exact opposite. It eliminates parasites and disease causing organisms that fish have naturally lived with their entire life and was given to them from their Mother.
This gap of the fish from meeting disease organisms completely eliminates the fish from staying immune and it becomes weak as it's immune system, which is a big part of it's physiology is gone.
Then, if the fish lives through quarantine and is fed non living food and no living bacteria and is exposed to no parasites, it's fate is sealed and it must try to live out it's life in a bubble because anything it encounters will kill it.
I could have quoted your entire post but I didn't think there was a need. I kind of like you anyway.
There is no doubt that excellent food and conditioning helps fish from developing disease.
This is wrong. Excellent food and conditioning does not keep a fish from developing disease. Immunity keeps a fish healthy and only being exposed to those things will get a fish immune.
Of course the fish first has to be in great condition and that condition is breeding condition. Only healthy fish can spawn as spawning, growth and immunity are the three things a healthy fish does.
All healthy fish spawn and they do it every few days or weeks. Female fish constantly fill with eggs, but only if they are in the best shape. Part of that great shape is immunity.
How many people on here have spawning fish that were quarantined? Not counting damsels because you need a School bus to run them over twice to kill them and they will live and spawn in damp oatmeal. I mean real fish.
How many quarantined fish die of old age without ever getting sick? Old age for most of the fish we keep is 15 or 20 years. I have some 26 year olds but they are clownfish so I don't count them for the reasons I mentioned.
If our fish die from anything else besides jumping out, being bullied or starving and we failed. They should all die of old age. Mine do and I am not that smart. Good looking maybe, but not smart.
By the way. I hope no one here feels that I am arguing with anyone. I don't argue, i am to old and to set in my ways for that. I am an ancient warrior but I don't do that any more. We are just discussing and I realize that there are many ways to do this. Not as good as mine.........No,,just kidding
I just have been doing it since they invented dirt so I figure I may have accidentally learned something along the way. But then again, maybe I am lucky.