Do tetras need to be in a school?
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OP
OP
Tetras and other schooling and shoaling fish school to avoid predatory fish, safety in numbers, as well as some fish use schooling behavior for hunting. It is in their DNA so they "expect" to be in a group. Byron is better at explaining this haha
You seemed to have answered your own question. I can speak from my experience in keeping tetras and barbs. A couple of weeks ago, I kept just a few neons as they were survivors from a larger group...and then I recently tripled the number and they were out and about more when in a larger group and tend to swim together. I also have the same experience with serpae tetras and harlequin rasboras....at least 6 is recommended and a larger group is even better if your tank size allows. Just check compatibility with other tank mates if in a community tank. My 35 gallon hex presently has 3 harlequin rasboras, 10 neon tetrons, 4 black skirt tetras, one dwarf gourami, and one bushynose pleco. The pleco is fine alone, the sole drawf gourimi is also fine alone. I need to up the harlequin rasboras to eight and maybe add a skirt tetra. Then I will be fully stocked.
My 29 gallon is mainly a tiger barb tank with eight tiger barbs. They definitely prefer to be in larger schools and they school pretty closely together. Also in the tank is one bolivian ram which prefers to be alone but often schools with the tiger barbs. Bolivian Ram can be territorial . If you have a large enough tank and lots of hiding places, two would be ok. My Bushynose pleco in that tank hardly ever comes out during the day but I imagine he is out and about at night.
My 5 gallon has the single Beta and he is king of his castle and he likes it that way. When I first got him , he had several tank mates and hid all the time. Now he is out and about all the time and has a big appetite., though I make sure not to overfeed him.
My 29 gallon is mainly a tiger barb tank with eight tiger barbs. They definitely prefer to be in larger schools and they school pretty closely together. Also in the tank is one bolivian ram which prefers to be alone but often schools with the tiger barbs. Bolivian Ram can be territorial . If you have a large enough tank and lots of hiding places, two would be ok. My Bushynose pleco in that tank hardly ever comes out during the day but I imagine he is out and about at night.
My 5 gallon has the single Beta and he is king of his castle and he likes it that way. When I first got him , he had several tank mates and hid all the time. Now he is out and about all the time and has a big appetite., though I make sure not to overfeed him.
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I dont understand what are you trying to ask.
Tetras need to be kept in groups.
In the wild tetras are found in huge schools consisting of thousands of individuals. They have lived like this for thousands or even millions of years. If you isolate fish (or any animal) that normally live in groups, they stress out and usually die prematurely.
All tetras should be kept in groups of at least 10 or more so they can have some company. Even 10 fish is a tiny number compared to what they would naturally live in. If you can afford it and have tank space, keep them in groups of 20-30+.
In the wild tetras are found in huge schools consisting of thousands of individuals. They have lived like this for thousands or even millions of years. If you isolate fish (or any animal) that normally live in groups, they stress out and usually die prematurely.
All tetras should be kept in groups of at least 10 or more so they can have some company. Even 10 fish is a tiny number compared to what they would naturally live in. If you can afford it and have tank space, keep them in groups of 20-30+.
Colin is right..the more the merrier...you'd do better to have one or maybe 2 compatible large schools in a tank than to have several smaller schools of various types that might get more stressed out. Just make sure to not overstock your tank which can increase ammonia levels and require more frequent and larger water changes. Better to understock than overstock. My 29 gallon tank is mainly a tiger barb tank and they school nicely and don't act aggressive amongst themselves.
Although I take the suggestions "with a grain of salt" , I use the site “Aquadvisor” to get a rough idea of stocking levels in my tanks. They have gotten better with time. But ask the knowledgeable folks here if in doubt on stocking levels.
Although I take the suggestions "with a grain of salt" , I use the site “Aquadvisor” to get a rough idea of stocking levels in my tanks. They have gotten better with time. But ask the knowledgeable folks here if in doubt on stocking levels.
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Retired Viking
Fish Connoisseur
I also believe that some fish like tetras need to be in a shoal of at least 6 or more the better. I have had neon, ember, red eye and glow light tetras and I have seen how they behave and group together especially when something scares them. They need to group together to feel safer. When ever something new is introduced into the tank they schooled together in their shoals. I saw this when adding new fish or making a major change in the tank. Once they relaxed then they would swim alone or in small groups. It is like the human fight or flight response to danger. I have a least 10 to 15 of each type.
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OP
OP
I made the thread in request of another member on another thread who does not believe that they do and wanted a discussion on another thread.
Tony blazer
Fish Fanatic
Well gentleman this question should have been can a pair of Tetris (various kinds) thrive in a community tank with other compatible Tetris and other species. Is there any science with factual statistical data that will proof that this fish will not thrive due to the lack of numbers in their school. That is the question that the OP should have expressed.
This come from a debate we we're having on another thread. Yes schooling fish will look cooler and some will be more active in large numbers but is there any real science saying that a pair will not thrive in a tank with other compatible tetras and other fish species. The answer is no only theories presumptions assumptions and experience. It's my experience is yes they can thrive as long as you have compatible tank mates and a good tank environment setup based on natural habitats like plants rocks and water flow ECT.
This come from a debate we we're having on another thread. Yes schooling fish will look cooler and some will be more active in large numbers but is there any real science saying that a pair will not thrive in a tank with other compatible tetras and other fish species. The answer is no only theories presumptions assumptions and experience. It's my experience is yes they can thrive as long as you have compatible tank mates and a good tank environment setup based on natural habitats like plants rocks and water flow ECT.
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Oh.. now I get itI made the thread in request of another member on another thread who does not believe that they do and wanted a discussion on another thread.
All info here is actually accurate. They do need to be in groups as schoaling fish (not schooling) fish. They will group with other tetra types if needed to form a schoal and feel safe in a community tank.
Waterstrider
Fish Fanatic
I’d say they’re at higher risk for stress and disease, so they absolutely need each other.
While I get everyone talking about group safety and fighting etc. this is not the only reason they school. Socialization is so ingrained with them that many types even move together to maintain safety from strong currents or water temp fluctuations in the wild. They also trigger each other’s eating behaviors by seeing other fish go for food. Most even group breed! If that last one isn’t social, I don’t know what is. But basically it plays on every factor in their lives.
While I get everyone talking about group safety and fighting etc. this is not the only reason they school. Socialization is so ingrained with them that many types even move together to maintain safety from strong currents or water temp fluctuations in the wild. They also trigger each other’s eating behaviors by seeing other fish go for food. Most even group breed! If that last one isn’t social, I don’t know what is. But basically it plays on every factor in their lives.
There is more to shoaling fish than just looking nice in a group. There is an inherent expectation in the DNA of the species. There have been relatively few scientific studies, perhaps because it has not seemed necessary to "prove" the obvious, but there are a few. And their results support the inherent need for a shoal; I'll return to this further on.
Most aquarists, especially those starting out, have fairly small tanks. So minimum numbers of a species becomes an issue. Most knowledgeable sources will advise "x" minimum but having more will improve the overall health of the fish. Safety in numbers is certainly one aspect, and depending upon species there can be hierarchial aspects. Fish communicate visually, but also chemically. Fishg release phermones that others in that species can "read," and allomones that fish in other species can read.
How does a fish "know" to avoid "x" or "y?" It is programmed into their DNA. And that gets us to the crux of the issue.
Every species of freshwater fish on this planet has evolved over thousands of years to function in a very specific environment. "Environment" as I use the term here means every aspect of the fish's existence, from the water parameters to the habitat properties to the number of that species living together--all of this is programmed into the DNA. The fish "expects" a very specific environment and its metabolism and physiology will only function well when it has that environment. Forcing it out of that "safety zone" has serious consequences. Primary among these is stress.
Biology Online defines stress thus: "The sum of the biological reactions to any adverse stimulus—physical, mental or emotional, internal or external—that tends to disturb the organisms homeostasis; should these compensating reactions be inadequate or inappropriate, they may lead to disorders." Each species of fish has evolved within a specific environment and the physiological homeostasis only functions well within that environment. This greater dependence upon their surrounding environment is why fish are more susceptible to stress than many other animals (Wedemeyer, 1996). Stress makes it more difficult for the fish to regulate the normal day-to-day physiological functions—the homeostasis—that are essential to its life. The effects of stress on fish are very complicated physiologically, and are often subtle. There may or may not be external signs discernible to us—it can continue for weeks and even months, sometimes up to the point when the fish just suddenly dies. The reasons for this are involved, and beyond the scope of this post but I would be glad to explain if asked.
The fish’s homeostasis only functions well within the species’ natural environment. A normal lifespan is virtually impossible if the fish’s environmental needs are not met to some extent. Dr. Paul Loiselle, an authority on cichlid fishes, writes "It is inhumane to deprive any animal of an element it regards as critical to its well-being, and totally naive to expect normal behavior in its absence." Shoaling fish expect to be in a group, and they will without question be under stress without this inherent need being met.
The few studies on this issue have shown that fish in too small a group tend to exhibit increased aggression as their way of dealing with the problem. Aggressive fish become more aggressive, and normally peaceful fish become aggressive to varying degrees. Sometimes the fish may react the opposite, by withdrawing and basically wasting away. By the time these symptoms occur, the internal damage has been done and it is not reversible.
Some species require more than the often-cited "six." Tiger Barbs and Serpae Tetra both need no less than 8-10 in the shoal. Those species where five or six are recommended minimums will always be healthier physiologically with more. The physical space of the aquarium is another factor. Too small a physical space from the fish's perception also causes stress.
There is a big difference between surviving and thriving. Neither can really be observed, because most fish will attempt to make the best of whatever situation we force upon them. By the time it is obvious, it is too late.
Most aquarists, especially those starting out, have fairly small tanks. So minimum numbers of a species becomes an issue. Most knowledgeable sources will advise "x" minimum but having more will improve the overall health of the fish. Safety in numbers is certainly one aspect, and depending upon species there can be hierarchial aspects. Fish communicate visually, but also chemically. Fishg release phermones that others in that species can "read," and allomones that fish in other species can read.
How does a fish "know" to avoid "x" or "y?" It is programmed into their DNA. And that gets us to the crux of the issue.
Every species of freshwater fish on this planet has evolved over thousands of years to function in a very specific environment. "Environment" as I use the term here means every aspect of the fish's existence, from the water parameters to the habitat properties to the number of that species living together--all of this is programmed into the DNA. The fish "expects" a very specific environment and its metabolism and physiology will only function well when it has that environment. Forcing it out of that "safety zone" has serious consequences. Primary among these is stress.
Biology Online defines stress thus: "The sum of the biological reactions to any adverse stimulus—physical, mental or emotional, internal or external—that tends to disturb the organisms homeostasis; should these compensating reactions be inadequate or inappropriate, they may lead to disorders." Each species of fish has evolved within a specific environment and the physiological homeostasis only functions well within that environment. This greater dependence upon their surrounding environment is why fish are more susceptible to stress than many other animals (Wedemeyer, 1996). Stress makes it more difficult for the fish to regulate the normal day-to-day physiological functions—the homeostasis—that are essential to its life. The effects of stress on fish are very complicated physiologically, and are often subtle. There may or may not be external signs discernible to us—it can continue for weeks and even months, sometimes up to the point when the fish just suddenly dies. The reasons for this are involved, and beyond the scope of this post but I would be glad to explain if asked.
The fish’s homeostasis only functions well within the species’ natural environment. A normal lifespan is virtually impossible if the fish’s environmental needs are not met to some extent. Dr. Paul Loiselle, an authority on cichlid fishes, writes "It is inhumane to deprive any animal of an element it regards as critical to its well-being, and totally naive to expect normal behavior in its absence." Shoaling fish expect to be in a group, and they will without question be under stress without this inherent need being met.
The few studies on this issue have shown that fish in too small a group tend to exhibit increased aggression as their way of dealing with the problem. Aggressive fish become more aggressive, and normally peaceful fish become aggressive to varying degrees. Sometimes the fish may react the opposite, by withdrawing and basically wasting away. By the time these symptoms occur, the internal damage has been done and it is not reversible.
Some species require more than the often-cited "six." Tiger Barbs and Serpae Tetra both need no less than 8-10 in the shoal. Those species where five or six are recommended minimums will always be healthier physiologically with more. The physical space of the aquarium is another factor. Too small a physical space from the fish's perception also causes stress.
There is a big difference between surviving and thriving. Neither can really be observed, because most fish will attempt to make the best of whatever situation we force upon them. By the time it is obvious, it is too late.
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I think it is important to point out that we are discussing schoaling fish here and not schooling fish. Schoaling fish stay in the vicinity of the group but may swim away a little to grab food, etc. Schooling fish are much more in sync, as one switches direction, they all do. They stay in a tighter group.
It seems that a lot of this discussion hinges on the definition of "thrive".
Yes small numbers of fish, that in the wild would normally be in large groups (either schools or shoals), can survive apparently quite happily in the small tanks we allow them. This survival can mean they grow to full size & live long lives - is that thriving?
Very few people will be able to give them real world conditions, so what we are beholden to do is give them the best conditions we can both environmentally & socially, i.e. water conditions and tank mates.
Any schooling/shoaling fish should be bought with that in mind - just buying them by how "2 of these will look good with a couple of these" is not the right way to go. If that means you only have a couple of "attractive" species in your tank so be it; that can still be a very spectacular, captivating tank to watch.
The science IS there that proves that schooling/shoaling fish are that for a reason - it is not a choice by a fish to be social! They will ALWAYS be better off if given the best conditions we can afford them. We should be keeping fish for the fishes sake, not just for us to look good.
If you just want to watch a few individuals from loads of species in a small space get a screensaver, a fish tank is a living breathing ecosystem and should be treated as such.
Although I can also see the argument that should we be keeping fish anyway - not a discussion for here.
Before anyone asks I've been keeping/breeding tropical freshwater fish since I was 11 years old (49 years ago now
), worked in several aquatic shops when I was younger, and before I moved was a keen member of my local aquarist society with a passion for all things aquatic; so I'm not some "newby blow-in" - I've had my share of successes & disasters and overall more successes I'm glad to say.
Yes small numbers of fish, that in the wild would normally be in large groups (either schools or shoals), can survive apparently quite happily in the small tanks we allow them. This survival can mean they grow to full size & live long lives - is that thriving?
Very few people will be able to give them real world conditions, so what we are beholden to do is give them the best conditions we can both environmentally & socially, i.e. water conditions and tank mates.
Any schooling/shoaling fish should be bought with that in mind - just buying them by how "2 of these will look good with a couple of these" is not the right way to go. If that means you only have a couple of "attractive" species in your tank so be it; that can still be a very spectacular, captivating tank to watch.
The science IS there that proves that schooling/shoaling fish are that for a reason - it is not a choice by a fish to be social! They will ALWAYS be better off if given the best conditions we can afford them. We should be keeping fish for the fishes sake, not just for us to look good.
If you just want to watch a few individuals from loads of species in a small space get a screensaver, a fish tank is a living breathing ecosystem and should be treated as such.
Although I can also see the argument that should we be keeping fish anyway - not a discussion for here.
Before anyone asks I've been keeping/breeding tropical freshwater fish since I was 11 years old (49 years ago now
), worked in several aquatic shops when I was younger, and before I moved was a keen member of my local aquarist society with a passion for all things aquatic; so I'm not some "newby blow-in" - I've had my share of successes & disasters and overall more successes I'm glad to say.Most reactions
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