Question on water change

[Lisak1]

Somebody needs to tell my fish - they didn't get the message!

 

[Meyer Jordan]

I just read this article about "diluting fish growing hormone through water changes, to avoid stunting the fish growth!" I've never read this before, I'm just curious to know what you think

https://www.kokosgoldfish.com/TheImportanceOfWaterChanges.html

I dearly love these internet articles that espouse some wild idea without any supporting evidence, references or identification of terms.
On this subject, a growth-inhibiting hormone, there is absolutely no, nil, zilch scientific documentation that such a compound exists. As with all other chemical communication substances such as pheromones, this substance would be classified as a semio-chemical. Much work has been done on this subject and the existence and effect of these chemicals on all animals, not just fish. Many substances have been isolated and identified. Not so with this 'growth-reduction hormone'. Exactly one (1) scientific paper has been written on this subject. It failed to draw any attention from the scientific community and quickly began gathering dust on a shelf. This mystery hormone has never been isolated or identified.
As with many things in science, the use of common sense goes a long way. If this substance did indeed exist, then fish that shoal or school would exhibit growth reduction as a general rule.....doesn't happen.
If this substance did indeed exist, intensive Aquaculture would not be possible for the goal here is to bring as many fish to marketable size in the shortest time. Such a mystery substance would make this concept economically unfeasible due to very poor production results.
And, if this substance did indeed exist, why is it (and this has been proven) do Goldfish achieve maximum growth and size at a density some would describe as overcrowding.
Typically the growth rate difference of fish in a pond is directly related to the amount of food consumed by each fish. Unless each fish consumes the identical amount of food on a daily basis, there will be obvious differences in growth rate.

 

[Lisak1]

Unless each fish consumes the identical amount of food on a daily basis, there will be obvious differences in growth rate.

Genetics has to play a role, too, right?

 

[Meyer Jordan]

Genetics has to play a role, too, right?

Of course, but for a hobbyist not as big a role as one would think. Entirely too many other factors involved in determining growth rate. If a Koi is genetically predisposed to attain a final mature length of 3 feet, then this Koi will reach that length. It is all of the other factors that determine how long it will take for this Koi to reach this goal.
For example, it is not commonly mentioned that Koi that are adapted to Northern latitude climates will attain a greater mature size than a Koi adapted to Southern latitude climates even if their genetic blueprint is identical.

 

[Mucky_Waters]

Exactly one (1) scientific paper has been written on this subject. It failed to draw any attention from the scientific community and quickly began gathering dust on a shelf. This mystery hormone has never been isolated or identified. .

Tell me a little more about this (1) scientific paper, do you have a link?

 

[Meyer Jordan]

Tell me a little more about this (1) scientific paper, do you have a link?

I believe that this is the paper I was referring to. It is certainly old enough to be.

http://scholar.google.com/scholar_u..._xvThmrD-E_B9egG4w2mIc1jw&nossl=1&oi=scholarr

 

[Mucky_Waters]

I believe that this is the paper I was referring to. It is certainly old enough to be.

http://scholar.google.com/scholar_url?url=http://www.aquahobby.com/etc/pdf/Chemical%20Communication%20in%20FW%20Fish.pdf&hl=en&sa=X&scisig=AAGBfm17R_xvThmrD-E_B9egG4w2mIc1jw&nossl=1&oi=scholarr

You might enjoy reading this paper http://jeb.biologists.org/content/jexbio/203/9/1477.full.pdf
It was referenced in this article http://injaf.org/the-think-tank/do-fish-grow-to-the-size-of-their-tank/ under the
Hormones & Pheromones paragraph which is also interesting and has a few other references.

 

[Meyer Jordan]

You might enjoy reading this paper http://jeb.biologists.org/content/jexbio/203/9/1477.full.pdf
It was referenced in this article http://injaf.org/the-think-tank/do-fish-grow-to-the-size-of-their-tank/ under the
Hormones & Pheromones paragraph which is also interesting and has a few other references.

Thanks, I read this paper a few years ago. The article that cites this paper is one of the examples of how easily a statement that is not quite true can become the basis for a wide belief.
GABA (and somatostatins) are indeed growth inhibiting hormones that are produced by Goldfish and other fish as well. The 'glitch' is in the ensuing conclusion is that the release of these hormones affects other fish. A little further reading reveals that these are internally released hormones (not pheromones) and only affect the fish whose physiology releases them. The release of these hormones within a fish does not affect the fish next to it, since these chemicals are not released into the water column. I did extensive research on this subject a few years back and I could find no supported reference anywhere that these hormones are indeed ever released into the water column thereby affecting other fish. It is much like you getting excited and getting an Adrenalin rush. It would not initiate an adrenalin rush to a person sitting next to you, at least not chemically.

 

[MitchM]

It doesn't make any sense why fish would have chemical defences against other fish that would be too diluted in a natural setting to be effective.

 

[Usman]

It doesn't make any sense why fish would have chemical defences against other fish that would be too diluted in a natural setting to be effective.

Good question il discuss this further with my mom shes Prof of Marine biology but think how fishes find eachother , identify gender and spawn in large waters , that it self is evidence that its effective even when visibility is zero , today its pretty well established that they exist , 15 years ago it was ambiguous , i have read in almost all the research papers and books on these topics they use this phenomenon .How do fish know that a female exists and it has eggs ready to be fertilized in rivers lakes small ponds .. Olfactory system , fishes use this to stay in school aswell or to find other mates which lives separately .

Three categories of pheromones can be discerned based on their function: anti‐predator cues, social cues, and reproductive cues. Each of these categories comprises pheromones that can induce “primer” effects (developmental and/or endocrinological changes) and/or “releaser” effects (strong behavioural changes). A handful of fish pheromones have been chemically identified and all are remarkably potent.
​

i was reading this recently How do fish know if they're swimming in the right school?... briefly

Dr Ashley Ward, a fish biologist at the University of Sydney. "A fish can smell itself, and recognises others with the same smell,"​

 

[Meyer Jordan]

Good question ur question answers it think how fishes find eachother , identify gender and spawn in large waters , that it self is evidence that its effective even when visibility is zero , today its pretty well established that they exist , 15 years ago it was ambiguous , i have read in almost all the research papers and books on these topics they use this phenomenon .How do fish know that a female exists and it has eggs ready to be fertilized in rivers lakes small ponds .. Olfactory system

Three categories of pheromones can be discerned based on their function: anti‐predator cues, social cues, and reproductive cues. Each of these categories comprises pheromones that can induce “primer” effects (developmental and/or endocrinological changes) and/or “releaser” effects (strong behavioural changes). A handful of fish pheromones have been chemically identified and all are remarkably potent.
​

The existence of pheromones in the animal world are not in question. What is being questioned is the belief held by some that fish release a substance (you can label it a pheromone, if you care to) that affects the growth rate in only certain other fish within their specie. This may be speculated about but no such substance has ever been isolated and/or identified.
When one considers that the specie of fish that is the subject of this discussion is Common Carp (Cyprinus carpio/koi) then certain other factors need be considered for such growth control to be even possible in the wild.
-Carp are riverine fish. Any pheromone or other chemical that is released would only affect those carp that are downstream so there is no real advantage to the releasing fish unless the pheromone is a sexual signal or predator signal.
-Carp are naturally shoaling (rarely schooling) fish, so group crowding is not an unnatural or threatening state for them, hence no reason for the release of any purported growth inhibitor.
-And here is the big one, IMO, Since it is known that these purported growth inhibitors are produced internally, why would this same chemical not affect the fish that produced it? Why are big fish the only ones with this purported ability?
The claim of the existence of such chemicals as one of the reasons supporting water changes is empty since no proof (scientific or logical) has been offered that conclusively supports such existence.

Are there any other non-supported reasons for water changes?

 

[Usman]

not to offend any one but today if ur rejecting pheromones then u have outdated information as it was not well established few years ago , u can might want to read this book , its not full on google

Fish Pheromones and Related Cues
https://books.google.com.pk/books?id=ldm6BQAAQBAJ&lpg=PA12&dq=how do fish find each other&pg=PA141#v=onepage&q&f=false

Abstract
Fishes commonly use reproductive hormones and their precursors and metabolites as “hormonal pheromones” that induce important behavioral and physiological effects in conspecifics. In goldfish, the best understood example is that periovulatory females release sex steroid and prostaglandin pheromones that increase male hormone levels, sexual behaviors, ejaculate volume, sperm motility, and paternity. Although such responses to released hormonal compounds have been described in only a dozen species, olfactory recordings indicate that several hundred species from major orders (Cypriniformes, Characiformes, Siluriformes, Salmoniformes, and Perciformes) are extraordinarily sensitive to water-borne hormonal compounds. Moreover, a number of these species discriminate a variety of hormonal compounds through multiple, highly specific olfactory receptor mechanisms, suggesting that, despite the limited chemical diversity of hormones per se, hormonal pheromones might be species-specific. The discovery of hormonal pheromones has fundamentally changed our concept of fish reproduction by illustrating how endogenous hormonal signals that originally evolved to coordinate reproductive processes within the individual have been co-opted as exogenous odorants that synchronize reproduction among conspecifics


http://onlinelibrary.wiley.com/book/10.1002/9781118794739



Pheromones are chemical cues that pass between members of the same species that convey specific, adaptive information. These cues, and related chemicals whose function are less well defined, are especially important to fishes because of their aquatic environments and complex behaviors. Pheromones are also of increasing interest in both basic and applied aspects of fish biology because they can be used to manipulate fish behavior and may explain phenomena such as fishery collapse. Fish Pheromones and Related Cues provides a timely synthesis of this growing body of research in freshwater and marine species and explores everything from how these chemical signals evolved, are produced, released and then processed, and finally to potential applications in fish culture and conservation.



Fish Pheromones and Related Cues opens with a useful overview on the theory of chemical communication and definitions. Chapters then progress by examining the biological importance of pheromones in inter- and intra-species communication, the role these chemical cues play in a variety biological functions from reproduction to predation, and then how they evolved and are detected and recognized by fish nervous systems. Final chapters provide valuable insight into how pheromones can be measured, how pheromonal disruption can explain effects of environmental pollution, and lastly how they pheromones are being applied in real-world efforts to culture fish species and to conserve our wild populations and control invasive species.

 

[Meyer Jordan]

not to offend any one but today if ur rejecting pheromones then u have outdated information as it was not well established few years ago , u can might want to read this book , its not full on google

Fish Pheromones and Related Cues
https://books.google.com.pk/books?id=ldm6BQAAQBAJ&lpg=PA12&dq=how do fish find each other&pg=PA141#v=onepage&q&f=false

Abstract
Fishes commonly use reproductive hormones and their precursors and metabolites as “hormonal pheromones” that induce important behavioral and physiological effects in conspecifics. In goldfish, the best understood example is that periovulatory females release sex steroid and prostaglandin pheromones that increase male hormone levels, sexual behaviors, ejaculate volume, sperm motility, and paternity. Although such responses to released hormonal compounds have been described in only a dozen species, olfactory recordings indicate that several hundred species from major orders (Cypriniformes, Characiformes, Siluriformes, Salmoniformes, and Perciformes) are extraordinarily sensitive to water-borne hormonal compounds. Moreover, a number of these species discriminate a variety of hormonal compounds through multiple, highly specific olfactory receptor mechanisms, suggesting that, despite the limited chemical diversity of hormones per se, hormonal pheromones might be species-specific. The discovery of hormonal pheromones has fundamentally changed our concept of fish reproduction by illustrating how endogenous hormonal signals that originally evolved to coordinate reproductive processes within the individual have been co-opted as exogenous odorants that synchronize reproduction among conspecifics


http://onlinelibrary.wiley.com/book/10.1002/9781118794739



Pheromones are chemical cues that pass between members of the same species that convey specific, adaptive information. These cues, and related chemicals whose function are less well defined, are especially important to fishes because of their aquatic environments and complex behaviors. Pheromones are also of increasing interest in both basic and applied aspects of fish biology because they can be used to manipulate fish behavior and may explain phenomena such as fishery collapse. Fish Pheromones and Related Cues provides a timely synthesis of this growing body of research in freshwater and marine species and explores everything from how these chemical signals evolved, are produced, released and then processed, and finally to potential applications in fish culture and conservation.



Fish Pheromones and Related Cues opens with a useful overview on the theory of chemical communication and definitions. Chapters then progress by examining the biological importance of pheromones in inter- and intra-species communication, the role these chemical cues play in a variety biological functions from reproduction to predation, and then how they evolved and are detected and recognized by fish nervous systems. Final chapters provide valuable insight into how pheromones can be measured, how pheromonal disruption can explain effects of environmental pollution, and lastly how they pheromones are being applied in real-world efforts to culture fish species and to conserve our wild populations and control invasive species.

Not to offend anyone, but some need to hone their reading skills.


My first sentence in Post #175 was:
"The existence of pheromones in the animal world are not in question."

And I might point out that nowhere in what was quoted in Post #177 is the word 'Growth'.

 

[budgenator]

It doesn't make any sense why fish would have chemical defences against other fish that would be too diluted in a natural setting to be effective.

Just wild speculation, but if a koi could put out a pheromone that inhibits other koi's growth, that would give the emitting fish an advantage in feeding melees. Very likely such a pheromones primary effect would be to induce passivity in other Koi and the secondary effect would be growth inhibition; a bully pheromone might be an apt description. The pheromone might not even direct inhibit growth, just feeding. Very likely genetics would play a role in how sensitive an individual fish would be to the pheromone.

If such a pheromone existed, it would only need to be effective in close proximity to other fish, such as the typical carp feeding melees. The unnatural conditions of our ponds could easily concentrate the pheromone. This would explain why people often find that their normally skittish koi come out and frolic during and after water changes.

 

[Mucky_Waters]

It doesn't make any sense why fish would have chemical defences against other fish that would be too diluted in a natural setting to be effective.

Fish, and other creatures, produce and release chemicals (hormones. pheromones, steroids, whatever) that effect themselves and each other, this fact is undeniable. Most of these chemicals released in minute quantities in nature are quickly diluted and washed away but even in the minute quantities they are produced they still are measurable and can effect themselves and or other the fish in close proximity. Concentrate fish in a condition where these chemicals can not be diluted or washed away it makes perfect sense that they are going to have more of an effect on the surrounding fish in those confined spaces. This seems like easy logic to follow, but still it's easy to ignore or deny if you don't really have a vested interest. Fish breeders on the other hand do have a vested interest and years of accumulated experience so I'll only quote the one portion of the article link I posted earlier.

Fish breeders have demonstrated that large frequent water changes can aid good growth as these dilute and/or remove some of the growth inhibiting hormones such as somatostatin. Mark Brumell (PFK interview with Jeremy Gay, 2012) recommends an unlimited supply of fresh water for optimal growth in goldfish breeding.

Still, I do agree that in typical backyard ponds that have plenty of plants, low fish stocks, and receive plenty of rain, water changes are much less crucial and may even be totally unnecessary, and there is even the possibility that they could do more harm then good if done improperly.