How to "age" an Oscar?

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FINWIN

Alligator Gar
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I'm trying to determine the age of my Oscar, Brick. He was 2 inches in size back in December of 2018. Currently at 11 inches. About what age is a 2 inch Oscar?

Age at maturity?
 
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I'm trying to determine the age of my Oscar, Brick. He was 2 inches in size back in December of 2018. Currently at 11 inches. About what age is a 2 inch Oscar?

Age at maturity?

Jexnell Jexnell
pops pops
 
While I have not raised Oscar fry, my Sagittae took two months to get an inch, I am thinking around four to get to two inch.

Unlike a lot of other species Oscar's are late bloomers, not reaching sexual maturity till a year and half old, after gaining 99%of their final adult size.

So let's say it was four months old when you got him, add in the the six months in your tanks puts him just under a year, not yet fully mature, still a teenager.
 
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While I have not raised Oscar fry, my Sagittae took two months to get an inch, I am thinking around four to get to two inch.

Unlike a lot of other species Oscar's are late bloomers, not reaching sexual maturity till a year and half old, after gaining 99%of their final adult size.

So let's say it was four months old when you got him, add in the the six months in your tanks puts him just under a year, not yet fully mature, still a teenager.

Thanks. I've heard everything from 2-4 months for 2 inches, so I was trying to do the math...I figured less than a year. So the 'slow creep' growth happens after that? (when they start bulking out) I've heard of old O's getting huge.

It might also explain all the pit digging lately.
 
Well all fish never stop growing, just slows way down.

It was the same with Toni, about the one year mark started bulking up instead of gaining length. 20180404_233558.jpg
 
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The problem with trying to age oscars (or any cichlids for that matter) by size, is the stocking, how they are reared, and most important the water change process by which they were raised.
If the person raising oscars does two large water changes per week, the oscar might grow twice as fast as a person doing one water change per week. So style and attention to water quality when being raised can slow or speed how old the size might appear
I have seen crowded oscars in a 20 or 30 gallon tank, in LFSs tanks appear to stay 2 inches for months (or longer), but once someone buys two out of that bunch, and puts them in a lightly stocked tank, doing lots of water changes, they may have a major growth spurt.
That time crowded, with only a few water changes can skew any aging. A 2" oscar in a LFS may already be a year old.
 
The problem with trying to age oscars (or any cichlids for that matter) by size, is the stocking, how they are reared, and most important the water change process by which they were raised.
If the person raising oscars does two large water changes per week, the oscar might grow twice as fast as a person doing one water change per week. So style and attention to water quality when being raised can slow or speed how old the size might appear
I have seen crowded oscars in a 20 or 30 gallon tank, in LFSs tanks appear to stay 2 inches for months (or longer), but once someone buys two out of that bunch, and puts them in a lightly stocked tank, doing lots of water changes, they may have a major growth spurt.
That time crowded, with only a few water changes can skew any aging. A 2" oscar in a LFS may already be a year old.

Would body shape be an indicator of maturity once they get to a certain size? I've seen some larger oscars with huge triangle shaped heads disporportionate to their bodies. Others I've seen have heavier bodies with a large head slope (the head is smaller in ratio to the body).
 
I don't know about age, but distorted oscars seem to be turned in quite often, flared gill covers, deformed heads, or covered in HLLE scars.
I believe here to.....just as with growth.....it has more to do with the water quality is raised in (or lack thereof).
Most being dumped into a tiny tank, with barely enough water changes to keep a couple guppy's alive (if performed as some average aquarium lit states) it's no wonder there are so many.
 
I agree there are too many unknown variables to really give an age by size.
We don't know how long the breeder had them.
We don't know how long it sat in the LFS waiting for you to buy it.

I'm my case I know the Wet Spot sells out and gets new Oscar's every month, two at most. So the unknown is breeder time.
 
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