Does aquarium size stunt growth?

[Malcontent]

I want my fish to grow like those square watermelons from Japan.

 

[CNDReef]

I believe size matters. I bought the same fish as my friend 6 or so years ago and mine is tops 4” and his is at least 6”
My tank is smaller.

 

[Dan_P]

I want my fish to grow like those square watermelons from Japan.

I believe you are onto something. This might make SPS coral shapes more interesting.

 

[Xanthurum]

My .02 short answer is that aquarium size affects fish growth. How exactly is a mystery. Most notably in fish that can get larger like Angels and Tangs. Oddly enough even when given ample space some fish will grow larger than others of the same species. I’ve seen the same species in the same size but different tanks grow to different sizes. Like 2 Powder Blue Tangs both in different 180 gallon 72 x 24 x 24 tanks for over 5 years and one was about 5” and the other was like 7”, but why? They were both about 2.5” when purchased and both fed nearly identical diets so why the size difference?

I currently have a purple tang that was given to me by a friend when they were moving out of state. He got it as a less than 2” juvenile and it lived in his roughly 200 gallon tank for over 3 years. In that time it only grew to just over 4”. It has been living with me now for over 6 years in my 160 gallon and I’d be surprised if it was over 4.5” which is half as big as purple tangs can get and it’s 10 years old. This fish is fat and happy and has always had plenty of room to stretch its fins and yet it is tiny compared to others I’ve seen that have been housed in smaller tanks. I’ve seen a tiny juvenile purple tang grow to over 6” in 2 years time in a 120 gallon 48 x 24 x24 so why did mine stay so small?
Enough of that, the real interesting thing will be seeing if moving my tiny 10 year old purple tang will suddenly have a growth spurt when he finds himself in the new 600 gallon tank I’m about to get!?!?!?

 

[Flame2hawk]

There’s no question that size of tank maters. Probably as important as nutrition and stress caused by stocking density and mates. Interesting though that I’ve had same fish starting off same size receive the same diet and water cleaning regimen. The one in the tank 4x’s as big grew faster and the other hasn’t caught up. Maybe I’ll switch one with the other and see what happens.

 

[Paul B]

It certainly affects many, but not all fish. If you keep fish long enough it is obvious. Many of my fish live for 10 years and I have a couple of fireclowns for 32 years. They are about 2 1/2". In the sea they get tripple that size.

My hippo tangs also live about 10 years and I have also seen them in the sea twice the size of mine.
One of my first fish was a Percula Clown. I had him in a 40 gallon tank for 7 years where he grew to about 2". I have seen them in the sea about 6".

But I have put in local New York sea robbins, flounders, eels and a remora and they will get huge no matter what size the tank.

I feed clams, live worms and other foods from the sea and most of my fish are spawning so I know they are healthy and fed correctly. :beaming-face-with-smiling-eyes:

 

[Stigigemla]

Different fishes are different. Both in tanks and in the wild.
I have seen the results from a test fishing of adult yellow tangs and they were of different size.
The age varied from around 8 for the most to 39 years and i am not that sure of the size but i believe it varied from 12 to 16 cm.
The adult size of most fishes has a natural variation.
From what i have seen grows a hippo tang to 8 or 10 cm in a 36 gallon tank instead of 30 to 40 cm in the wild.
Chromis virides males grow to 10 cm in big tanks just as in the nature.
I had a Mandarin fish of 10 cm and that size they never reach in nature.
Tilapias grow very big in murky breeding tanks and are sold as human food.
They dont seem to be small because of bad water and extreme crowding.

 

[jasonrusso]

My .02 short answer is that aquarium size affects fish growth. How exactly is a mystery.

I had a very smart guy who runs a local coral farm (and was a pharmaceutical chemist) explain it to me. I have never read it anywhere else, but it makes total sense if accurate.

Fish release a species distinct enzyme in their waste. The higher the concentration of the enzyme (smaller tank), the slower the growth. The lower the enzyme the faster the growth.

 

[Ardeus]

Neolamprologus multifasciatus in captivity get to twice the length that they reach in the wild.