Large Discus Stunting Smaller Discus?

[sciaccaj20]

Hello -

I think I read, maybe in TFH, that larger Discus give off some kind of chemicial that can stunt the growth of smaller Discus. Does anyone know if this is true? Let me know. Thanks.

John

[jpjagged]

i think you may be referring to a hormone that the discus puts out of its body via slime coat? and i have read somewhere also that a tank that doesn't get regular water changes can accumulate this in the water and it will inhibit growth of the fish in that water

not exactly positive on this though

[ShinShin]

Jack Wattley refers to a growth inhibiting toxin, and specifally stated one time that he never called it a hormone, that he believes donimate discus release inhibiting the growth of the discus around them. He also saw this demonstarted with the tadpoles of the Dart Frogs he raises as a hobby. In a talk he gave in at the ACA Convention in Fort Worth, Tx. a few years back, he called this "toxin" an alkaloid.

I am one who believes this theory of his. I have taken a dominate male, also the largest, out of a tank of growouts approaching breeding age, and immediately another male's growth begin to show. On one particular occasion, the 1st dominate male was put with a breeding female, and the next male to emerge actually surpassed the 1st male in growth. This was not a food issue, as some will think. All the fish had all they could eat.

Mat

[sciaccaj20]

Thanks for the info. It does make sense, and I'll pass this info. to a buddy of mine.

[Eddie]

Wow Mat, that is very interesting. Thanks for information


Eddie

[Don Trinko]

I am a non believer; I believe it has more to do with how much food the lowest in the pecking order gets and the stress on that fish.
All of this IMO Don T.

[Tavio]

I think theres some truth to this theory. I am fairly new to discus but by no means new to cichlids and have kept them for some time now. I have noticed this in the past. The most recent experience was with some Geophagus I had. Out of a group of 4 I had 1 adult agressor. I pulled him out and not long after another Geo rose up. The other 2 also grew a bit. I also agree that food was not an issue. They where fed a generous amount of spirulina brine shrimp and blood worms on a daily bases. They where some piggies. Not sayin anyone is wrong just my personal experience.

[ShinShin]

Don,

I've disproved your theory many times. I even stated an example.

Mat

[Don Trinko]

Larry; I did say IMO, You have a lot more experience than I do. I just don't see how in nature any "hormone " or "toxin" could influence the Amazon river.
Don T.

[ShinShin]

Don,

Discus don't live in the Amazon River. Don't you the that the "Godfather of Discus" would have considered food? He has doe so many experiments in that area. What I thought was particularly strange at the talk he gave, there were several people who have argued against such a toxin (we've discussed it many times on many forums over the last decade) in the audience, and none spoke up when given the oppurtunity. Why? Were the convinced? Did they not want to be embarrassed? I don't know. All I know is that they sat there with there mouths shut.Mat

[trebor69]

Don,

Discus don't live in the Amazon River. Don't you the that the "Godfather of Discus" would have considered food? He has doe so many experiments in that area. What I thought was particularly strange at the talk he gave, there were several people who have argued against such a toxin (we've discussed it many times on many forums over the last decade) in the audience, and none spoke up when given the oppurtunity. Why? Were the convinced? Did they not want to be embarrassed? I don't know. All I know is that they sat there with there mouths shut.Mat

no matter where you want to say they live.... I think it is safe to say it is usually in a volume of water easily great enough to severely dilute the 'mystery toxin'


probably because it would be like arguing the existence of Bigfoot...nobody can prove their side so why bother

hey....maybe Bigfoot gave the secret toxin formula to the the Loch Ness Monster...lets ask him

[1077]

I am no expert but it passes my understanding given the frequency and volume of water changes, as to how any alkaloid or hormone could accumulate to any measureable degree. But I remain open to anyone who could enlighten me and shall reserve the right to disagree.:argue:

[ShinShin]

What is not understood is exactly what mechanism this subtance uses to perform its work, and how little or much is needed. It is possible that being in it presence alone triggers the mechanism. Amount may play very little role here at all. Meaning, if you do a 40, 50, even 90% water change a day, it is still always there.

Anyway, like I said, there were plenty of people at Jack's talk besides me, many whom disagree, but in his presence kept their mouths shut. It would probabally be the same if Jack were to post his theory here himself. I know, email or call him and ask him all about it. He's a great guy to talk with.

Mat

[dpt8]

I do not mix discus of different sizes because I do not think it looks very good. IMO, I think it looks much better to see discus of the same size grouped together. Probably that's why I have 9 discus tanks. My discus are grouped by variety and size. :9) Al and Mike Degan's fish are similarly grouped. Looks cool and gives smaller discus a better chance to grow out. :9)

[1077]

Maybe it is similar to those who can simply look at chocolate and put on pounds. In any event, it is an interesting theory.:)

[YSS]

I am one who believes this theory of his. I have taken a dominate male, also the largest, out of a tank of growouts approaching breeding age, and immediately another male's growth begin to show. On one particular occasion, the 1st dominate male was put with a breeding female, and the next male to emerge actually surpassed the 1st male in growth. This was not a food issue, as some will think. All the fish had all they could eat.

Mat

These experiments suggest that the dominant male somehow affect the growth of other discus in the tank, but, in my opinion, doesn't prove that the dominant male produces toxin that inhibit growth of other discus. If the dominant discus produces toxin, wouldn't that also adversely impact his own growth? Also, in nature where a large volume of water is present, this toxin would have almost no impact, so doesn't make sense that this is discus' natural protection/survival (or whatever you want to call it) mechanism. What you described sounds very similar to african cichlids coloring up and showing the dominance by displaying the color. But again, I am no expert and I am just stating my opinion.

[Don Trinko]

I think no one questioned Jack out of respect. Most people are resonably polite and would not want to make a scene.
I definatly do not know as much abought discus as many of the people on this forum but on this forum I have read abought many factors that affect discus growth. To determine witch of these factors applies to a particular tank full of discus would be dificult since almost everyone is trying to give their discus what they consider to be optimum conditions.
A scientific study with the "hormone/toxin" isolated and then a controled experiment with no "hormone/toxin" in some tanks and added to others would make me a believer. Don T.

[blue acara]

I think this theory is a possibility, after all there is always a dominant and usually larger fish in any group...
As Mat said it may be enough just to be close to this 'toxin' for a short time and in low dose for it to trigger an effect. This would have to be the case in the wild.
Bleher suggests that there is the 'alpha' in a discus group, and that the job of the alpha is to attract the attention of predators..in doing so protecting the group as a whole. By making the others smaller and itself larger it can achieve this more effectivly. If it dies a new 'alpha' will quickly come to the fore. Just my thoughts.

[Darrell Ward]

As stated, it's a theory. Not scientific fact. I tend to take theories with a grain of salt until proven. :)

[Roxanne]

....
As Mat said it may be enough just to be close to this 'toxin' for a short time and in low dose for it to trigger an effect. This would have to be the case in the wild.
..

I can have no opinion either way but it is interesting to hear you experts discussing these things..we novices learn so much and appreciate the time you take to educate.., is it possible that the other fish could detect that 'toxin' and just move away from the fish in the wild, like a squid spits ink? But, in a tank has no escape from the constant hormone spitting (I know that doesn't sound grammatically correct), which even with water changes could never be as dilute as a habitat in the wild? If there IS such a hormone I mean..And if there is why can't another male spit it back at the first fish and make him sick right back? If that sounds like a dumb question, nobody answer it!

I have noticed my dominant male will peck at the other males, and intimidate them at feeding time but he doesn't do it to the female. Then, when I corral him, in a square net in the same tank to give the others a break, the next dominant male starts to boss the next discus down in the pecking order and they are exactly the same size and are in fact 'brothers'. And I have noticed there is a definate pecking order. But, none of them is thin or growing any different to the dominant male. The twin males do not boss each other when they are in a tank alone together, only when the female is in there too. I hand feed them 3 times/day and I make sure they all get an equal feed. If I don't leave my hand in the tank during feeding, the dominant male spends all his feed time chasing the others around the tank, so he's hardly getting a lion's share for himself! He only THINKS he's the Alpha male, he is actually SMALLER than the other males. If there was such a hormone, surely the lower males would lose weight regardless of being fed the same. I feel like if I don't intervene, they wouldn't get much food at all, and would just stay in the corner of the tank, and grow thin. I only do water changes every second day, so with one to three males releasing some kind of 'toxin' they would all be anorexic by the next waterchange yeah?

That shoaling effect when fish detect the next fishes movement using electrical charges (:confused:whatever) infers to me that they may be able to influence each other in all kinds of ways we have yet to discover...so come on guys, get your lab coats on...

Roxanne:)

[MSD]

This is a totally bogus assertion that has no evidence on the internet nor with any other free swimming fish in the sea. There is the arguement that corals on a reef, which are fixed for the most part, fight for territory with cysts and stingers. But this all happens in close proximity and since discus are wild in comparatively large water bodies the amount of toxin would be huge. Plus as mentioned it would affect all discus in the area resulting in areas of stunted discus IN THE WILD. Wonder what Heiko would think. And about Jack Wattley, he did much research and forgot more then I will ever know, but he also recommended breaking off a piece of sandwich and sharing it with your discus. And I heard that with my own ears.

[rfeiller]

ShinShin, this type of thing carries over into most of the animal kingdom whether it is a fish, wolf or elephant in the presence of a dominate male the testosteron live drops in the lessor males. this is true of the dominant and lessor females.

it has to do with the pack, herd, school of fish, survival of the fitest. the smaller fish will be stunted because of these limiting and sometimes lethol substances. fish wholesalers have experienced very expensive lessons particularly with salt water reef fishes.

[discussmith]

I think for all of you who are interested and/or want more info, I thought of this very issue back when I read Wayne Leibels Cichclidophiles article in the May issue of Tropical Fish Hobbyist on page 36. "Who's in Charge Here? Cichlid Piddling Contests." He reports on three experiments in a study and lists the references used. Very educational and quite convincing concerning the Mozambique tilapia as a study candidate. At least there seem to be some correlations to the observed results of non scientific experiments with the species with which we are concerned, and will certainly make one consider all the possibilities in making their own judgement.

[Patr1ck]

I have 4 discus in my 90 gal. Three of them have been there for about a year. The fourth one has been there for @8 months. The dominant one who is (or was) the biggest, is one of the original 3. The newest one went from the 2nd smallest to about the same size as the big one. He grew at a faster rate than the others. He is shortly on his way to passing up the dominant one. From what I've seen in my tank, I dont know if the hormone thing is accurate. Maybe some fish have a more agressive(alpha) gene than others and in that, they consume more food thus getting bigger along with their appetites and forcing others to stay smaller from eating the leftovers. Survival of the fittest at work in the aquarium. :bounce:

P

[rfeiller]

there are several things, water changes, which are females, which are males two seperate pecking orders. genetics of fish.

with wild discus and some of the strains i had the females grew fastest initially. others it was the males. it is difficult to do a quantitative and qualitative analysis with so few animals with unknowns.

this isn't a copout to my former statemet. i still stick with my previous comment for generalities.

be grateful for good stock

[Discus-Hans]

I know I'm not Mr. Wattley and I know I'm not even allowed to walk in his shadow, and NO I was not on Mat's meeting, but.........

I've 2.5" 3" 4" and 5" in one system and all we do is scoping Discus to the next tanks because they grow. No scientific hola hoepa, just practice experience,

Hans

[Roxanne]

Humans come in all shapes & sizes. Our individual growth isn't dependant on testosterone/growth hormone levels in those around us. Couldn't it be that some of any species of animal you could name, are predisposed to grow larger anyway, and therefore naturally assume the alpha role? I know we're talking about marine creatures which may be completely different & Who am I to question the workings of creation, but I ask, the larger elephant becomes the dominant male because he was genetically predispositioned to outgrow the alpha, or because he hormoned the other guy into smallness?:confused:

[Ed13]

Humans come in all shapes & sizes. Our individual growth isn't dependant on testosterone/growth hormone levels in those around us.
But, hormones and pheromones are resposinble for behavior by an individual and those that respond around it. In a particular situation hormones and the behavior from it can present and alpha and submisive individuals.

Couldn't it be that some of any species of animal you could name, are predisposed to grow larger anyway, and therefore naturally assume the alpha role?
Size is not always nor necessarilly the fatcor that determines this. In some species size and strenght might give the edge to an individual, but sometimes behavior, disposition, personality can and does dominate even in species where the larger animals have an advantage although obviously a very large difference in size and strenght is hard to beat. Of course I'm talking in general terms and not necessarilly separating aquatic and land animals

I know we're talking about marine creatures which may be completely different & Who am I to question the workings of creation, but I ask, the larger elephant becomes the dominant male because he was genetically predispositioned to outgrow the alpha, or because he hormoned the other guy into smallness?:confused:
Actually elephants follow a matriarch. This female, usually the oldest female and dominat (not necessarily in size) is responsible and leads the pack which consists of other submisive females and their young, they even expulse males when they reach a certain age. Males on the other hand roam free and do battle each other for the rights to mate with the females, usually the higher they are in the hierarchy the better. Obviously if there is a size difference between males the advantage goes to the larger one. But, when they are equally matched (same for fighting fish) the disposition, personality, tolerance to pain, tenacity and aggresiveness dictates the victor.

I do get what you mean though I'm just being a smart a... :o
But, I guess you could argue that hormones may lead to push over and limit the size of other individuals not directly but as a consequence. Pheromones on the other hand trigger breeding and may indicate dominance by themselves. When other individuals become submisive they relinquish territory, food rights, and even breeding rights. Therefore increasing the size, strenght, and offspring of the dominant individual.

How does this relate to discus? I don't know...:p lol

[rfeiller]

ed15,
young male elephants will stop their sexual aggression and attempts to mate in the presence of an older male. this method has been used to control uncontrolled young male elephants in the wilds of africa

it has been repeatedly proven in wolf packs. its also applies to other animals testosterone levels.

what the substance is or isn't in fish it does exist. whether you can measure it or not. so much we do not understand in the animal kingdom. science has only scratched the surface.

elephants are a matriarchal society. study how that works. there is a definite pecking order; what generates the power to one over the other?

i have worked with too many fish to not believe that it exist. science is too far in it's infancy to convince me otherwise

[VIOLIN33]

HOW MUCH DO DISCUS GROW A MONTH,WITH GOOD FOOD AND WATER CHANGES?? THANKS

[Roxanne]

...sometimes behavior, disposition, personality can and does dominate even in species where the larger animals have an advantage...

I can say I have a BD that THINKS he's the biggest......and the larger male turks are actually intimidated by him...go figure:confused:


I do get what you mean though I'm just being a smart a...

I know you do, Thats cool mate, I have that smart a** gene too!:)


Pheromones on the other hand trigger breeding and may indicate dominance by themselves. ..QUOTE]

OK Without getting too graphic though it is relevant given the subject matter, when women with 'cycles' of differing times of the month co habitate, their 'cycles' eventually 'line up' & begin to occur at the same time. I know this is true because when three of my buddies and I shared a place, it happened. Any bloke living with more than 1 female over child bearing age in the house can verify this! I have heard it explained that hormonal secretions females all emit is the stimulus for this "phenomenon". Why does it happen? What is it's purpose? In contrast, take the powers of attraction in humans. If we were to take the example of say 1 couple who meet physically & fall 'in love', & 2. a couple who meet say online and could have therefore not traded hormones and they 'fall in love'. Is it hormonal or is it in the head?

I heard recently new thoughts on the effect hormones have on the divorce rate (don't groan, it was on Oprah!) and whether or not if a woman is taking contraception when she meets what becomes her future partner, has an effect on mutual attraction type hormones, if she becomes pregnant or stops taking the contraceptive pill, something happens to the attraction hormones and they aren't attracted to each other anymore. Therefore implying that if you are taking a contraceptive pill when you meet somebody, your hormones are confused & u are not necessarily choosing your ideal mate or who your hormones would choose if they were in the right mind.:D....Although I feel this could have more to do with the fact that the guy is an insensitive type and she just get's sick of him:D or vice versa(possibly)

It's true. There are many things that cannot be explained or even understood yet. It hasn't been that long since humans found out that I think it's blue whales, communicate with each other over great distances of ocean. How incomprehensible is that?

[QUOTE]young male elephants will stop their sexual aggression and attempts to mate in the presence of an older male...this method has been used to control uncontrolled young male elephants in the wilds of africa

I heard that too. Interesting to know if it is because he hormones him into submission, or the younger phant just senses not to "go there"...
I guess the question is, what MAKES the younger phant submit?

Knowledge is power....more power to us all!;)

[Don Trinko]

I think the younger male "submits" because the older male is bigger and tougher, Not because of any hormones. Same with discus pecking order; It's not always the biggest but the most assertive ( maybee mean) . Don T.

[Roxanne]

Well Don Trinko, THAT would explain my relentlessly mean & bossy little BD!;)

[Ed13]

The pressesnce of the large male elephant alters the behaviour of the whole herd though, so it's kinda hard to guess if its sight, smell, sound, or the interaction of the herd with it's pressence. Young breeding age males could be stopping for what I call "the bull syndrome", submisive males sneak a mating with willing females when possible before they have to face the wrath of the bull, so they stop as soon as they detect their pressence. Happens with sea lions, walrus, hippos etc.

As far human attraction having to do with hormones, the "smell" of your inmune system is very important. Scientists believe that partners are chosen by the resemblance of the smell to your own parents.

Discus are fish though, don't for a harem but are not monogamous either, yet form shoals were in the wild opportunity to feed can't follow dominance becuase of space and quantity of food. They also live in a flowing medium, water, and vast moving in the case of the Amazon so toxins or any other chemicals are carried away fast, why would they evolve the need for it then? It's kinda hard to put it together through comparisons and logic alone how would, if any hormones, pheromones or toxins come into play. Close observation over a long time is needed. But, perhaps sight, sound and pressure variations picked up by the lateral line are more important we think...

[ShinShin]

BTW, Andrew Soh mentions this phenomenom in his book "Discus - The Naked Truth". While stating that no scientific research has been done on discus, that his theory is similar to "frog syndrome", where something in the frog's urine supresses the growth in the weaker tadpoles in its enviroment. Evedently, Jack Wattley is not the only person that noticed this with frogs. It has its own recognized syndrome. Now does Andrew mean frog or tadpole is the question.

Mat

[William Palumbo]

Kind of hard to compare a frog to a fish...even a tadpole...two different creatures. There will always be some Discus bigger than others in a tank....they are the most aggressive eaters. Seems with all that water in the Amazon...ALL wild adult Discus shoud be the same size...as there would be NO hormones involved...size being dependent mainly on feeding (or genetic disposition)aggressiveness and food intake. As I am sure some are more proficient eaters/hunters of food....Bill

[Roxanne]

Kind of hard to compare a frog to a fish...even a tadpole...two different creatures.Bill

Hi Bill, I can see both sides, but they are both water creatures and we are, I thought, exploring the possibility of whether or not a water creature can emit "something" that is powerful enough to affect the immediate environment around it and it's "rivals". I can see there are a few possibilities either way.

Although, this is besides the point, I thought the discus only live in the tributaries of the Amazon and not the Amazon itself...I might have that wrong though..



..frog syndrome...It has its own recognized syndrome.

But, with Larry Mat's reference to the study on frogs, by none other than Mr Wattley, that seems to confirm to me that even if it does/does not happen in Discus, it happens!

Rox

[fishman1978]

I just keep learning & learning:)

[stevey87]

I read similar things about goldfish. I'm not sure about other fish but they said they did find particular substance that inhibits the growth of other fish around them.

[hottandcoldd]

Very very interesting discussion. Can't wait for a scientific and solid proven answer to this question >.<