Growth rate vs max size potential

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philipraposo1982

philipraposo1982

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Speaking in general, is it safe to assume that a fish that is growing at a faster rate then what would be consider the normal, will end up being a larger fish?

Is there a relationship between the two or is it completely seperate?

I realize this is all anecdotal but I would still like to hear your experience.

Main reason I am asking is because my female festae wet pet has been doing lots of growing in her first year and continues to show signs of above average growth rates. Wondering if she will end up being a larger than average female too.

She is even developing a small nuchal hump and is gaining in her terror attitude.
 
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From my own experiences only... I'd say growth speed def has a play on overall size... I could be wrong but my female jack grew extremely fast and is almost 9 inches full grown and all information I've read says females generally get 6 to 7 inches.... where ive had slower growing fish reach smaller overall sizes.... I have 2 raphael cats aswell... all information I've read says they grow extremely slow... some saying they've had theres for 2 years with only an inch growth while my 2 are very active do to less hiding spot and get lots of food... have grown an inch in length in less than 3 months... will see as time goes on as to how big they grow in the end... hopeing for a couple massive fat monsters as I've seen they are capable of achieving very large sizes
 
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Fish grow all there lives, a species will have a size bracket that's considered normal but the older the fish then generally it will be at the upper end of that bracket. So trying to speed grow a fish might give you better initial results but could mean the fish dies earlier and never reach its potential.
Andy woods amphilophus labiatus and chancho are around the same age if I remember correctly. The labiatus grew at a much faster rate than the chancho, it hit about 14 inch and slowed right down, would have to put it on the weighing scales to detect the growth now. The chancho which I thought was a bit of a runt, just keeps piling on the lbs, even at over 6 years old is still growing at half inch to 1 inch a year and is now bigger then the labiatus.
I personally don't think early initial growth necessarily means that the fish will end up bigger. If you want a huge fish give it the best conditions so it lives longer.
 
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dan518 said:
Fish grow all there lives, a species will have a size bracket that's considered normal but the older the fish then generally it will be at the upper end of that bracket. So trying to speed grow a fish might give you better initial results but could mean the fish dies earlier and never reach its potential.
Andy woods amphilophus labiatus and chancho are around the same age if I remember correctly. The labiatus grew at a much faster rate than the chancho, it hit about 14 inch and slowed right down, would have to put it on the weighing scales to detect the growth now. The chancho which I thought was a bit of a runt, just keeps piling on the lbs, even at over 6 years old is still growing at half inch to 1 inch a year and is now bigger then the labiatus.
I personally don't think early initial growth necessarily means that the fish will end up bigger. If you want a huge fish give it the best conditions so it lives longer.
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My answer is off of experience with a few fish under what I think was great conditions.. your answer is probably the best answer to give!
 
dan518 said:
Fish grow all there lives, a species will have a size bracket that's considered normal but the older the fish then generally it will be at the upper end of that bracket. So trying to speed grow a fish might give you better initial results but could mean the fish dies earlier and never reach its potential.
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True only with respect to fish that have long life expectancy such as koi, sturgeon, marine shark, grouper, etc. that live as long as or longer than human. Most aquarium fish have short life: Tetras 3 to 5 years, live bearers, 2 to 5 years, cichlids, 5 to 15 year. They max out at half life and begin to decline gradually with no detectable growth for the remainder of their life. Long live fish, like tortoise and big snake, continue to grow throughout their long life and show no sign of aging or declining vigor and appetite.

Within the same genus, the larger ultimate size of the fish, the faster they grow. For example, among cichlids, Midas grow faster than Dempsey, and Damsey faster than rams. Across genus, the comparison is inconsistent. For example, clown loach grow slower than Dampsey, but CL ultimate size is twice as big. There are also gender difference in growth rate within species. For live bearers, females grow faster than males to ultimate bigger size. For cichlid, males grow faster than females, but not necessarily show the growth spurge at early stage. For example, my green terror juvies are about the same size for both sex under 2 inch, but then males begin to outgrow females after.
 
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I'm going to exclude trying to induce fast growth through so called power feeding, etc. and say ime the answer is yes, overall, with exceptions. I've seen it breeding and raising fry in most species I have experience with-- in spawns of most species you get a small number of (what I call) superfish, early on they're just bigger, often more colorful, and they often turn out bigger as adults. But you can also get sleepers, nothing special early on but also they turn out to be big specimens.

I sometimes see the same thing buying groups of a species to grow out, naturally one or two in a group may be more dominant, bigger in the group, etc., though not necessarily exceptional or max size for the species-- but sometimes you get one that tops out at the high end for a species.

This isn't in all species ime. Some, like O. lithobates Z rock (which I bred), consistently reached the same size for me as adults, 5.5 inches and not much more, with little difference between individuals. The other occasional exception is the runt, initially, that takes off at some point. Had it happen with some pigeon blood discus I grew out once, among the very early pigeon bloods. One of them came as a colorless, runty individual that grew very little the first few months, though it was feisty and held its own. It turned out to be the biggest, most beautiful adult in the group.
 
tiger15 said:
True only with respect to fish that have long life expectancy such as koi, sturgeon, marine shark, grouper, etc. that live as long as or longer than human. Most aquarium fish have short life: Tetras 3 to 5 years, live bearers, 2 to 5 years, cichlids, 5 to 15 year. They max out at half life and begin to decline gradually with no detectable growth for the remainder of their life. Long live fish, like tortoise and big snake, continue to grow throughout their long life and show no sign of aging or declining vigor and appetite.

Within the same genus, the larger ultimate size of the fish, the faster they grow. For example, among cichlids, Midas grow faster than Dempsey, and Damsey faster than rams. Across genus, the comparison is inconsistent. For example, clown loach grow slower than Dampsey, but CL ultimate size is twice as big. There are also gender difference in growth rate within species. For live bearers, females grow faster than males to ultimate bigger size. For cichlid, males grow faster than females, but not necessarily show the growth spurge at early stage. For example, my green terror juvies are about the same size for both sex under 2 inch, but then males begin to outgrow females after.
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Good points (with occasional exceptions). A lot of cichlids reach max size in two years, though they may live ten or more. Some put on a little more size the third year.

Cyphotilapia have a similar early growth rate to many other cichlid species, but they grow longer than most. Males often reach 6 inches the first year, they may add two inches the second year, inch or two third year, slow down after this, but keep growing. Males, especially, often keep growing until about 5, then stop or slow way down.

--I don't know as much about big Central Americans.
 
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In nature most cichlids don't reach full potential for many reasons, and quoted max sizes often represent that nature growth size in scientific descriptions.
With lots of water changes, and no predation, Central American cichlids will frequently grow larger in properly managed aquariums than in nature, and if females are prevented from breeding, (which uses up vast amounts of energy, and growth resources) will grow quite large, and show dominant features.
In nature I have seen 10" JDs, where in aquariums I have seen more than 12" old guys.
I saw a 10" to 12" firemouth in a large aquarium in Chicago.
In nature these older slower individuals are prime game for predators, and rarely last.
 
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All fish grow their entire life. Whether it slows down or not or how long it takes to slow down are all factors. But i have yet to read on a fish that doesnt have indeterminate growth. Most fish just put on mass after certain lengths but to say they stop growing is simply untrue
 
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