Fry vs. Juvenile

[gwand]

When does a fry officially become a juvenile fish? Does this vary by species?

 

[anewbie]

I don't think there is an official classification. My general thought is when mom tells the fry to get lost s/he is now a juvie BUT i have species where mom looks after her kids; i guess the metrics would be different from species that don't realize they have kids and for those species that eat their kids - maybe it is when they are too large to be eaten

 

[GaryE]

For me, they become juveniles when I peer at them desperately hoping for signs I have both sexes, but not seeing any yet. Then as they do sex out, it includes the period before they can breed.

It's subjective, but for most Cichlids, a month to six weeks? But that's only for me.

 

[anewbie]

For me, they become juveniles when I peer at them desperately hoping for signs I have both sexes, but not seeing any yet. Then as they do sex out, it includes the period before they can breed.

It's subjective, but for most Cichlids, a month to six weeks? But that's only for me.

I'm finding for my smaller dwarf cicihld the mother will care for the fishes with 2+ months but of course we can call them juvi before she tells them to go away if that makes people happy

 

[Back in the fold]

I think it’s like @GaryE said but , to me , also when they start looking like fish and not babies .

 

[anewbie]

I think it’s like @GaryE said but , to me , also when they start looking like fish and not babies .

You mean these angelfishes aren't juvi ?

 

[Back in the fold]

You mean these angelfishes aren't juvi ?

View attachment 359982

Nope . Those are fry . Juveniles will have the tall dorsal and anal fins .

 

[CassCats]

I've always gone with a couple combined physical changes. Once it starts looking like a fish and not a tadpole and has a semblance of markings to it, when the stomach contents are no longer majorly visible like a giant pouch, and finally when fin shapes change to resemble their respective species more.

Examples:

Fry hoplisoma paleatum

Juvenile

Fry Nematobrycon palmeri

Juvenile Nematobrycon palmeri

Fry ancistrus bodenhameri

Juvenile ancistrus bodenhameri

 

[emeraldking]

When does a fry officially become a juvenile fish?

To me most of the time would be when they're about half way to adulthood.

 

[anewbie]

To me most of the time would be when they're about half way to adulthood.

You know i was thinking about this comment. And i occurred to me that at least for me it depends on the species. I have a lot of young krobia xiguensis, mesonauta egregius, a. sp winkelfleck, a. wolli and a. sp bluketa i'm currently raising. Now the k xiguensis and m. egregius are larger fishes - 3 to 5 inch range and i think around 1 1/4 inch i would consider the krobia xiguensis to be juvi while the m. egregius which look more like their parents at 1/4 an inch than the krobia i would call fry - with the decider being the m. egregius are still in a more delicate stage. However to wait till they were 1/2 way to adult-hood well with the slow growing egregius that would be another 6 to 8 months which is a long time to be a fry

However for guppies and endler 1/2 way to adult hood would occur much faster.

 

[emeraldking]

You know i was thinking about this comment. And i occurred to me that at least for me it depends on the species. I have a lot of young krobia xiguensis, mesonauta egregius, a. sp winkelfleck, a. wolli and a. sp bluketa i'm currently raising. Now the k xiguensis and m. egregius are larger fishes - 3 to 5 inch range and i think around 1 1/4 inch i would consider the krobia xiguensis to be juvi while the m. egregius which look more like their parents at 1/4 an inch than the krobia i would call fry - with the decider being the m. egregius are still in a more delicate stage. However to wait till they were 1/2 way to adult-hood well with the slow growing egregius that would be another 6 to 8 months which is a long time to be a fry

However for guppies and endler 1/2 way to adult hood would occur much faster.

For sure it depends on the species how fast they'll grow up to half way adulthood. But there are even livebearers that take quite long before they'll reach adult. And then we're talking about juveniles that are about 6-8 months. And just sex out at a year or even over.

 

[GaryE]

I think I may have the perfect formula. When you think it isn't a fry anymore, it's a juvenile. It's a completely subjective category change. Some pike Cichlids stay with their parents til they are are well over six inches long. Technically, they'd be juveniles.

It's like people.

 

[gwand]

Yeah. I remember uncle Sidney lived with grandma until he was 40 years old.

 

[anewbie]

Yeah. I remember uncle Sidney lived with grandma until he was 40 years old.

Welll... Uncle sidney had a long life as a fry