Promote fish knowledge with fish ageing! Hoorah for PC

Waldo · Post by **Waldo** » 07 Sep 2005, 08:24

You know... I've gotten a plethora of information from this website and would like to thank PC for the tremendous help I've received here. HOORAH for PC.

I'd also kinda like to bring up a point. MANY information websites for fish tell the maximum size a fish gets and breeding information. What about age? I know fish differ. People should think if buying a fish like buying a cat or dog. Part of being an owner is being able to know if youâ??re going to need to put a fish in your will. I move to have PC help with this as I think it would help owners better understand that their fish is going to need a 300g tank in 7 months or 7years. What say yee ol' might PC?

Post by **Silurus** » 07 Sep 2005, 08:27

I move to have PC help with this as I think it would help owners better understand that their fish is going to need a 300g tank in 7 months or 7years.

Would that be age, or would that be growth rate?

MatsP · Post by **MatsP** » 07 Sep 2005, 08:39

I think Waldo is referring to growth rate, but I think it's valuable to have both an average age and some indication on "age to adult size". I do realize that most fish will continue to grow for (almost) their entire life, but the growth rate certainly slows down a lot when they reach something like 75-80% of "full-size".

--
Mats

bronzefry · Post by **bronzefry** » 07 Sep 2005, 15:33

Is there a difference between lifespan in the wild and lifespan in captivity? For instance, I have Pristella Maxillaris (sorry for the spelling). I was told that their lifespan is short, appx. 18 months maximum. I've had these fish now for 3 years. I did further reading and it turns out the 18 month figure is for Pristellas in the wild.

I would imagine there are some species that lifespan in captivity is an unknown. I guess the only way to find out would be to breed them and follow their lives. But, what if you acquire a wild caught fish and you don't know its age? How do you determine it?

MatsP · Post by **MatsP** » 07 Sep 2005, 15:38

Amanda,

That's two very good points.

Yes, the average lifespan in captivity (assuming good conditions) is much longer than in the wild.

And of course, on anything but fry, you would have a very hard time telling whether the fish was a big for it's age (i.e. younger than a guesstimate) or small for it's age and thus older than it looks. Impossible to say without cutting it up and analyzing bone-rings or something...

--
Mats

bronzefry · Post by **bronzefry** » 07 Sep 2005, 15:50

I've done internet searches after internet searches and it's quite frustrating. I found one site that gives generalizations, but I think those were the "in the wild" lifespans. It would be a daunting task to add tank-bred lifespans. I would imagine that since cats and dogs have been captive-bred for many generations, there's a good bit of info.
Amanda

racoll · Post by **racoll** » 07 Sep 2005, 17:46

a good rule of thumb is; the bigger the fish, the longer it lives. of course there are always exceptions.

Waldo · Post by **Waldo** » 07 Sep 2005, 18:08

I was aiming for both adult age and growth rate. To me while it would be interesting to know how old and fast they grow in the wild... it would be more benifitial to know about the aquaria rates. I also think adult age would be more important as you would automatically assume that the years divided by the length would give you a pretty ruff est of rate.

djw66 · Post by **djw66** » 07 Sep 2005, 20:31

bronzefry wrote:Is there a difference between lifespan in the wild and lifespan in captivity? For instance, I have Pristella Maxillaris (sorry for the spelling). I was told that their lifespan is short, appx. 18 months maximum. I've had these fish now for 3 years. I did further reading and it turns out the 18 month figure is for Pristellas in the wild.

I would imagine there are some species that lifespan in captivity is an unknown. I guess the only way to find out would be to breed them and follow their lives. But, what if you acquire a wild caught fish and you don't know its age? How do you determine it?

Bronzefry, though I have no idea as to their lifespan in nature, Neon tetras can live for 10 years or more in properly maintained aquariums, and it wouldn't surprise me if many of their characin cousins couldn't reach similar ages, despite their small size.

Forget about 25-year-old Jack Dempseys

Dave

Waldo · Post by **Waldo** » 07 Sep 2005, 21:06

See what I mean. Who knew that Neons would live so freaking long. Next time you go to the store you remember that they are going to live as long as 10 year... wow the things you learn

djw66 · Post by **djw66** » 08 Sep 2005, 02:26

Waldo wrote: See what I mean. Who knew that Neons would live so freaking long. Next time you go to the store you remember that they are going to live as long as 10 year... wow the things you learn

The odd thing is to my knowledge Neons live a decade or more when they are in larger groups (say, a dozen or more). Perhaps, like us, they experience stress when there are few of their fellows, and we all know people live shorter lives when constantly stressed.

My uncle here bought a 29-gallon aquarium in 1979, and I set it up for him. I got him two dozen Neons and a couple of cories (aeneus, I believe), a couple of husbandry books, and let him at it.

In '88 he was tired of the tank, as the walls and ornaments were covered with algae, but the Neons and cories were still going strong. I can only assume he changed the water regularly, but I know he fed them Tetra flake throughout their lives. The algae also must have contributed to purifying the water, as the world is filtered by algae.

He told me a couple years later he gave the fish to the local fish store, so they had to me at least 10 or 12 years old at that point.

It wouldn't surprise me if Bronze's Pristellas (Pristella=little saw) don't reach 8 or 10 years.

Taratron · Post by **Taratron** » 09 Sep 2005, 10:59

We have some blind cave tetras at work that are seeing their 14th year of life with us so far. They were over an inch long when we received them.

I love these fish!

bronzefry · Post by **bronzefry** » 09 Sep 2005, 17:37

10 year old Neons and 14 year old Blind Cave Tetras!

Good work! I recently purchased 3 new Zebra Danios because some of the 5-6 year-old ones died. I just couldn't have one swimming alone. These were the first fish I got from my brother. He purchased them as adults and kept them for 2-1/2 years. He handed them over to me 2-1/2 years ago. I'm glad I got 3 more because the old male is still breeding like a young 'un. The eggs are great foraging food for Aeneus Cories.

djw66 · Post by **djw66** » 09 Sep 2005, 21:18

Waldo wrote:I was aiming for both adult age and growth rate. To me while it would be interesting to know how old and fast they grow in the wild... it would be more benifitial to know about the aquaria rates. I also think adult age would be more important as you would automatically assume that the years divided by the length would give you a pretty ruff est of rate.

Waldo,
I just read in the most recent issues of Freshwater and Marine Aquarium thus:

'Crampton also found wild fish (Discus) to be relatively short-lived Ã¢â‚¬â€

Post by **Marc van Arc** » 17 Sep 2005, 19:59

Taratron wrote:We have some blind cave tetras that are seeing their 14th year of life with us so far.

Apparently not that blind.

sidguppy · Post by **sidguppy** » 18 Sep 2005, 10:39

Still got 5 Mochokiella; 2 are probably very young, but 3 were bought in 1986 as sub-adults, wich means they're about 21 years old or so!

my friend Pectorale recently lost the last of the ol' Synodontis nigriventris; this particular fish was bought by me as a group of halfgrown youngsters in 1984!

given the growthrate of this species they were 2-3 years old when bought wich means the last oldie kicked the bucket at 23 years old.....his remaining one was bought as a halfgrown baby in 1991 and doing fine.

currently I have a pair of granny's* from wich the female at least was imported as adults 20 years ago (the male 10 years later); The owner of that store -Dirk Verduijn- recently lost his oldest 11" granny, a fish wich he bought when setting up the store and building his big showtank. that was back in the early seventies and the granny's were imported as fully grown adults!

those Mochokids definitely are in for keeps

*S granulosus

bronzefry · Post by **bronzefry** » 18 Sep 2005, 16:25

I think the long lives these fish achieve to speaks a lot to the husbandry. Nice work!

I have so much to learn. I think it would be interesting to compare, at some point the way the lives of a species, such as one of Sid's Mochs, now living in a tank environment, and compare it's life to a wild Moch. I think it would be interesting to see the similarities and differences. I've read about the loss of certain sensory abilities in captivity. But, I'm sure there are other comparisons to be made. Would this be a longitudinal study? Maybe all of this has been done.

djw66 · Post by **djw66** » 18 Sep 2005, 21:25

bronzefry wrote:10 year old Neons and 14 year old Blind Cave Tetras! Good work! I recently purchased 3 new Zebra Danios because some of the 5-6 year-old ones died. I just couldn't have one swimming alone. These were the first fish I got from my brother. He purchased them as adults and kept them for 2-1/2 years. He handed them over to me 2-1/2 years ago. I'm glad I got 3 more because the old male is still breeding like a young 'un. The eggs are great foraging food for Aeneus Cories.

Bronzefry,

Thought you would find this interesting.

'(Zebra Danios') best age for breeding is about one year. At two years they are old. They seldom live beyond three years.'
â?? William T. Innes 'Exotic Aquarium Fishes', 15th Edition, 1953.

Proves that captive bred fishes, like your Danios, are much better suited, under proper care, which you obviously have, toward appreciably longer lives than they do as wild fishes, as written above. Yours have lived twice as long as their wild cousins.

Dave

bronzefry · Post by **bronzefry** » 19 Sep 2005, 14:19

This is interesting! Thanks, Dave.

Promote fish knowledge with fish ageing! Hoorah for PC

Promote fish knowledge with fish ageing! Hoorah for PC

Re: Promote fish knowledge with fish ageing! Hoorah for PC