Tangs in a tank

[Anonymous]

wombat - a standard 120 is 48x24x24.

vitz- Certainly the fish don't regulate their size by their own volition, but I think there is some other element at play here other than issues of general health. Where I live in the Catskill mountains there are plenty of tiny creeks that contain little tiny brook trout; perfectly healthy and breeding. Bigger creeks have bigger ones. I have no idea how this works...

 

[Mogo]

IME, fish reported as growing 8" long in the wild will not approach that size in captive conditions. I have seen that tank size has something to do with overall fish size in FW cichlid tank. In 12 years, my cichlids have not approached the sizes they supposedly reach in the wild. This also could have something to do with fish density, competition etc.
As I have had my SW swimmers only for about 2 years, it's too early for me to draw the same conclusion with them, but I think the same would hold true.

I also observe that fish do stop growing at some point.

In terms of fish voluntarily regulating their growth rate, no way. If so, maybe I can do the same. I would be one hell of a basketball player 8)

 

[Anonymous]

wombat - a standard 120 is 48x24x24.

vitz- Certainly the fish don't regulate their size by their own volition, but I think there is some other element at play here other than issues of general health. Where I live in the Catskill mountains there are plenty of tiny creeks that contain little tiny brook trout; perfectly healthy and breeding. Bigger creeks have bigger ones. I have no idea how this works...

well, for one-fish secrete a growth regulating hormone-that affects other members of their own species

example:

a batch of 20 fry are placed in a 20 gal. tank

a few of the fry start a growth spurt first-the other fry will always be smaller than the first ones that started to spurt first

remove those larger fry, -and another few will spurt, etc., etc.

my guess is that the further distance between individuals comes into play in the creek situation-less exposure, or exposure to a more dilute, growth supressing hormone from other species members

the effect is only on other fishes of the same species, and it's not 'voluntary' :wink:

 

[naesco]

According to Henry Shultz III, tangs in properly sized tanks reach normal growth.
Reefers who place their tangs in small tanks stunt the growth of their tangs.
He sets out the example of a blue tang which will grown normally at 2 iches per year for 5 years but will not reach it normal lenth of 12 inches in small tanks.

 

[Anonymous]

the concept of the physical size of any container having any affect on a fishes size is an old wives tale, a myth :wink:

it's like saying an elephant kept in a small cage will not grow to be a full size elephant-all other elements for the elephants health being provided for(like nutrition, and clean water)

no animal's size is affected by the physical size of its container :wink:

there's another issue at play

and it's a quality of environmental parameters thing

in a smaller system-more organic pollutants, (and anti growth hormones, etc) build up more rapidly in a system-it's these things that can affect the growth rate of fish

again-fish do not stop growing, ever-only the growth RATE will slow down,- it may even be imperceptible to your eye

take a 30 gallon tank-place an oscar, or a tang in it, and connect the 30 via a circulation system to a 1,000 gal tank-both will grow to full size, assuming the system is properly filtered/maintained :wink:

put either in a 150 gal tank, ignore the filtration/water quality, and both will get 'stunted'-due to the deteriorated chemical environment

put any oscar in a 20 gal tank, and change 20% of the water daily-you will raise it to full size-it won't be able to turn around comfortably in the tank,-but it will grow to full size :wink: i've seen it done


growth of any animal is a genetic 'program' that is affected by things like nutrition, and quality of the environment (biological/chemical), not by the size of it's 'cage'.


the tang's 'anti growth hormone' is most likely affecting itself, this will happen to any fish, as well, in a closed system that doesn't get enough water changes to dilute the hormones, or nitrates,phosphates, and other waste substances-

the purpose of the hormone, from an evolutionary standpoint, is probably to help minimize space competition between what would otherwise be larger individuals, in a reduced environment sized setting(smaller fish=less food needed, less waste produced per individual=less stress on a smaller environments further reduced resources)

 

[naesco]

Vitz I used to agree with you on this issue and we are still 80% right.
But I have now been convinced that I am 20% wrong.
PM me and I will give the source of this enlightenment :wink:

 

[fishfarmer]

Vitz,

Do you have any links to articles about this growth regulating hormone stunting fish growth?

DanConner,

IMO some of reasons the brookies are so small in the upland brooks is probably due to colder temperatures, less food, possibly less sunlight as well. The lower down the system you generally see warmer, richer habitats, which should yield larger fish. I think harsher winters play a role too :wink: .

I also wonder if genetics plays a part in stream systems, especially if the upland streams don't get a mixing with their bigger cousins downstream.

Given the optimum natural growing conditions for the fish in your tank, your fish shouldn't stunt IMO.

 

[danmhippo]

If given optimal parameter (excluding tank size), we should've never hear comments that their fish outgrow their tank!

 

[Anonymous]

Vitz,

Do you have any links to articles about this growth regulating hormone stunting fish growth?

DanConner,

IMO some of reasons the brookies are so small in the upland brooks is probably due to colder temperatures, less food, possibly less sunlight as well. The lower down the system you generally see warmer, richer habitats, which should yield larger fish. I think harsher winters play a role too :wink: .
I also wonder if genetics plays a part in stream systems, especially if the upland streams don't get a mixing with their bigger cousins downstream.

Given the optimum natural growing conditions for the fish in your tank, your fish shouldn't stunt IMO.

those are some of the environmental parameters that are always relevant to whether or not a fish fulfills its genetic potential-most of which are affectors of metabolism :wink:

i read the articles years ago in fama i believe-and the 'discovery' was from someone who initially was researching f/w angelfish-but the result/observation is easily duplicated under controlled experimental conditions, with all species of fish bred in captivity

i personally observe the phenomenon every single time my fish spawn/reproduce, and witnessed the same thing occur while working in a commercial polyaquaculture farm, and hatchery-in fact, one of the practices at the farm was to continually measure the fry's growth stages in the grow out ponds, to determine when to cull out the larger juvenile fish to larger ponds-the smaller fry would then also begin growing faster

(try sorting out hundred's of kilo's of carp fry by hand on a sorting trough while they zip past you all day long) :wink:

the statement about fish growing their entire life was from a fama column on fish trivia, from years back, iirc

just to clarify-ultimate size that can be reached by any animal is a genetic potential-size of a container just doesn't affect the relevant factors for utilization of that potential, chemical factors, or factors that affect chemical factors, do.(eat a crappy diet and suffer from malnutrition, you won't reach your potential-food availability, temperature, all those conditions affect this potential)

the only way i can think of to 'cheat' this potential is through hormone manipulation-again, a chemical affector :wink:

naesco-if you have info that has convinced you that the physical size of a container alone has been proven to affect fish growth, and not the 'inferior', or more quickly degrading,water quality issues typically involved/associated w/a smaller system-i'm sure everyone would be interested-no pm's necessary :wink:

 

[Anonymous]

naesco-in reference to your pm:

the question is -what is it about the size that's affecting the growth rate?

were all the chemical parameters compared/measured/altered on comparably sized tanks?

take fifty 200 gal tanks, with identical setups, but change the turnover rates for the water changes-if no difference is found, in final growth (not close to 5 yrs for a tang, more like 20 then i'd be convinced that there may be an issue, here

the evidence that such is not the case is far more overwhelming :wink:

and fwiw:

people post links to threads from one bb to another all the time, np :wink:

but, w/out even reading the article, i would have to see a study involving at least a thousand fish, with proper controls

i'll pose a different set of questions for you-too further illustrate my point :wink:


at which tank volume/size is the effect nonexistent?

do tangs in an open system in a public aquarium not grow to their full size? (in a tank, but w/constant turnover of clean, nsw)?

if you 'penned in' a school of tangs on a small reef patch w/netting, thereby limiting their 'roaming room', would they not grow to full size?

i think you should post the link in this thread-one should never be concerned about helping to exchange knowledge/opinions about knowledge from one bb to another :wink:

i've certainly done it here, and on the bb you mentioned :wink:

if i thought that a particular thread/post that i found anywhere on the net had relevance to a discussion about science/husbandry of fish-i'd post it here w/out a moments hesitation

 

[Anonymous]

Fish never stop growing, only the growth rate chages. Which is why you can use the otoliths (ear bones) to determine age. Although I'm not sure about the hormone idea in a creek situation. Wouldn't the concentration be so minimal anyway in a creek where water is constantly flowing past. It's like constant 100% water changes.

Another way to look at it, is unless a fish is crapping 100% of it's food, that food has got to go somewhere.

 

[reefsRcool]

welcome to the board. it is so refreshing to see a new person ask questions before hand instead of coming here saying i have killed ten fish in three days how can i fix it by saterday when my 12 corals come UPS.

don't be scared by the tang police but do have some respect. i am no tang expert but agree the Vlamingi is a definite no no. everything else IMO should be ok.

 

[Will C1]

on the size thing i have noticed that fish found in the inland lakes of michigan for instance a perch will only reach lengths of 6" or so but in the great lakes they reach a size of 12"-14" which i have never seen on an inland lake.

 

[wombat1]

Rover wrote:

Another way to look at it, is unless a fish is crapping 100% of it's food, that food has got to go somewhere.

It goes to metabolic costs as well...

 

[Garry thomas]

My god.....i think i could be going to the dark side. :lol: Mixing more than one of the arcanthurus sps, is really not a good idea, as i expected i knew there would be trouble, but not as much as i got. And thats in a 11 ft'r. I sold my sohal because he was getting a pain in the butt and very big. i purchased a clown tang /lineatus as a juv 4 months ago. He's now 7 inchs long, he is an even bigger pain. I'v always wanted a powder blue, so i got one........WW3 the clown went nuts, it's taken a month for the clown to except the p/b, luckily the p/b avoided ich and any real damage off the clown. My sailfin (veliferum) has got to go, thats gone huge in 2 years. And as much as i'd like a lipstick/naso i would'nt because of the size issue.
Damicodric you dont state reef, or f/o, i take it it's f/o. i for one know how much waiste these baby's produce. So try and be sensible with stocking tangs/surgeons in small tanks! :roll: