This thread is one of the best out there and it's great to hear civil discourse on both nutrition/immunity and QT.
I don't now about that. Right after every post that I don't agree with, I shoot holes in the posters avitar. Then I have to go to Best Buy and get another computer.
There is definitely such a thing as vitamin A hypervitaminosis in fish.
There may be and I am sure some researcher came up with that. But almost every meal fish eat another fish. Fish are full of oil and that oil is vitamin A. I think about 12% of a wild fishes food is vitamin A.
As I said, for years I injected it into prey fish to feed my carnivores. If they got hypervitaminosis they didn't tell me about it.