Yes, growth will always be on a curve. It may nearly level out at some point. And so accurate about including that its the avereage max size thats often quoted.
Growth rate vs max size potential
- Thread starter philipraposo1982
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Ive seen a 24” Oscar in Shedd Aquarium and an 18” Frontosa at the former National Aquarium in Washington DC. Both showed sign of aging with some deformity. Unlike human, aging fish don’t shrink, just deform. Size is based on eyeballing, and can’t be verified without measuring with a ruler.
Wouldnt an oscar that size be a reasonable argument FOR what ive been saying. Thats well above the listed max size. Odds are that yes the fish was ancient in oscar terms, but it obviously didnt just stop growing.
You are trying to hang on to your erroneous belief that all fish grow for life. No, only some long live fish appear to grow all life long, because it takes a long time for aging to kick in and stop growth. Short live fish age and die early, and you will never see monster size guppies, killfish or beta that live only 2 to 3 year. Salmon are big fish but live only 3 to 8 year, and once they breed, they die so there are no outlier monster salmon. Lake trout, a relative of salmon, can live 20 or more years and surprised big trout are occasionally hooked. The reason monster oscar is never seen in home aquarium is because most outgrow their home aquarium and died prematurely. In public aquariums with no cramped space, aquarists are shocked to see monster size oscar, iridescent shark, gar, etc that they don't expect to see in home aquariums.
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This is the, what, third time I've stated this-- I've been measuring, not eyeballing. Stop telling me I'm eyeballing. You do enough measuring and you get good at eyeballing, but with fish I've bred, and with some of my longer lived fish, specifically to see whether or how much they've grown as they've aged-- I've measured,
Anyway, let's set personal observations aside. You guys are forcing me to bring out the references--
http://www.dulvy.com/uploads/2/1/0/4/21048414/pardo_et_al2013_online.pdf
https://www.researchgate.net/publication/11941082_Paradigm_of_growth_in_fish
https://link.springer.com/article/10.1023/A:1006533531952
https://www.sciencedaily.com/releases/2006/11/061128083925.htm
All fish do not grow all their lives-- period. Most fish grow all their lives. There are known exceptions and, almost certainly, exceptions that have not been studied yet. Some species-- and besides those in science articles I've seen, by observation and measurement, I include a number of Malawi cichlids-- IF they do continue growing, 'almost cease to grow' and grow so slowly after a certain age that it's meaningless to a fishkeeper.
This isn't just a matter of small vs. large fish or short lived vs. long lived fish. There are small, short lived fish known by science to grow all their lives. Also, when you get into some of the science articles, because a species can potentially grow all it's life (indeterminate growth) doesn't mean a particular individual grows all its life. There's also discussion in some articles whether indeterminate growth is an interpretation based on most fish not reaching their potential longest lifespan for various reasons and whether the progressive slowing of growth as a fish ages ultimately stops if the fish lives long enough-- one could argue, though this isn't my argument, that if enough old fish of enough species were studied science would find they indeed eventually stop growing.
Anyway, let's set personal observations aside. You guys are forcing me to bring out the references--
http://www.dulvy.com/uploads/2/1/0/4/21048414/pardo_et_al2013_online.pdf
https://www.researchgate.net/publication/11941082_Paradigm_of_growth_in_fish
https://link.springer.com/article/10.1023/A:1006533531952
--This is the marine cardinal, not the Amazon cardinal. This is what I said earlier, growth in some fish becomes so minimal after a certain age that it's negligible, which is what I've seen in some species for myself-- by measuring, not eyeballing.
https://www.sciencedaily.com/releases/2006/11/061128083925.htm
All fish do not grow all their lives-- period. Most fish grow all their lives. There are known exceptions and, almost certainly, exceptions that have not been studied yet. Some species-- and besides those in science articles I've seen, by observation and measurement, I include a number of Malawi cichlids-- IF they do continue growing, 'almost cease to grow' and grow so slowly after a certain age that it's meaningless to a fishkeeper.
This isn't just a matter of small vs. large fish or short lived vs. long lived fish. There are small, short lived fish known by science to grow all their lives. Also, when you get into some of the science articles, because a species can potentially grow all it's life (indeterminate growth) doesn't mean a particular individual grows all its life. There's also discussion in some articles whether indeterminate growth is an interpretation based on most fish not reaching their potential longest lifespan for various reasons and whether the progressive slowing of growth as a fish ages ultimately stops if the fish lives long enough-- one could argue, though this isn't my argument, that if enough old fish of enough species were studied science would find they indeed eventually stop growing.
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Determinate and indeterminate growth are biological term to describe the growth profile differences between warm blooded mammal and bird versus cold blooded reptiles and fish. When an indeterminate growing fish or reptile approaches their life expectancy, the biological clock will kick in to stop growth, then die months to many years later depending on species. Technically, only a small number of fish like Salmon or all Cephalopod grow all their life because once they breed, they age and die in hours.
