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small tanks

Colin_T

Fish Guru
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A lot of people that come onto this forum have small aquariums, and they do so for various reasons. They could have financial restraints, lack of room, move a lot, or just don't want a big tank and don't want to spend a $1000 on a new hobby they might not stay with. Whatever the reason, it is up to them.

I have noticed that when people come on here asking for help with fish health issues, some of them get told (often in pretty abrupt terms) that their tanks are too small and that is why their fish are dying. This is often rubbish as the fish are usually dying from a disease, not a small tank. And whilst some of you will say the disease is caused by the stress that comes from living in a small tank, that is also rubbish. The diseases get brought into the tank by fish, plants, snails, water from a shop, etc, and the fish become infected with the pathogen. This can occur in a 20 litre tank or a 2000 litre tank.

I will agree that small tanks are more prone to fluctuating water chemistry and are more likely to have problems with ammonia & nitrite due to their smaller water volume. However, many people do cycle the tank without fish in, and those who don't can do big regular water changes to dilute the nutrient/ chemical build up. Having said this, if there are no disease organisms in the aquarium, the fish will not develop a disease simply from being in a small tank. The pathogens must be in the tank for the fish to become infected with them.

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Being told their tank is too small can be quite unpleasant for the person asking for help. Many people that are new to fish keeping come here looking for help and it is up to the more experienced fish keepers to OFFER ADVICE ABOUT THE PROBLEM. If someone's aquarium appears is too small for the fish they are keeping, you can SUGGEST their fish would probably do better in larger quarters. But try to be tactful about it and only mention it after you have answered or helped with the original problem.

People that are losing fish are stressed out enough knowing their fish are dying. If they are new to fishkeeping and have no idea what is causing the problem, that makes it worse. Do not add to their stress by having a go at them because their tank might be (in your opinion) too small.

In a perfect world you would not be able to buy a fish tank less than 6ft long, nothing would get sick or die and wild fishes would not be endangered. We don't live in a perfect world. People don't always get good advice when they buy a fish or a fish tank from a shop, and we should not have a go at them simply because they did.

Please, try not to have a go at new people who happen to have a small aquarium. Offer helpful advice and be tactful. Put yourself in their shoes for a moment and think about how you would feel if you had just bought a tank from a pet/ aquarium store and you go home, set it up and start losing fish. Then you find a forum that appears nice and friendly and helpful, and someone says "your tank is too small, that's why your fish are dying". If you didn't know any better, how would you feel?
 
And whilst some of you will say the disease is caused by the stress that comes from living in a small tank, that is also rubbish.
Really?

A juvenile fish growing up in a too-small tank can be expected to experience stunted growth, spinal deformities, atrophied muscles and other developmental heath problems.

Quite often the " small tank " is the problem.

When housed correctly in a 5 plus gallon tank with proper care a Betta can easily live 5 or more years, A breeder friend of mine has several that are 7 years old.

This is not a Betta tank
3052b74ea5483240877d2220c06b246e--fish-care-betta-fish.jpg


This is.
aWP76Ga.jpg


This is what a healthy happy Betta looks like
xUjl973.jpg


This is a unhappy Betta
firebreathingbettas-1-e1461408481790.jpg


Healthy happy females at feeding time

If these girls were stressed from being in too small a tank it would result in carnage.
 
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A juvenile fish growing up in a too-small tank can be expected to experience stunted growth, spinal deformities, atrophied muscles and other developmental heath problems.
Stunted growth can occur in any size tank and is related to hormones released into the water by the young fish in an attempt to slow the growth of those around it. Water changes counter that problem.

Lack of food is also a reason for slow growth in fry and in fact, lack of food will inhibit growth more than a small tank.
eg: I have 2 foot long tanks with 50-100 rainbowfish fry in. The fish are fed as much as they can eat 5 times per day and get a 50-75% water change each day. These fish are sold at 2-3 months of age and are the same size or bigger than the ones that come from normal suppliers/ importers. None of the fish have deformities from this environment. The only deformities seen are those the fry hatch out of the eggs with, (genetic deformities). And those are culled as soon as they are noticed. Generally I have no deformed fry growing up in rearing tanks.

Spinal deformities are caused by inbreeding and internal growths like TB & tumors.

Atrophied muscles are caused by muscle wasting diseases, not by moving around a small tank. People in wheel chairs have this problem in their legs because the muscles don't get used. If a fish is swimming around, it will not suffer from this.
 
@Colin_T This has been the best ever forum I've ever been on. Nobody has bashed me that I can think of. The only part I've ever seen people get testy about is of the OP isn't listening at all but continues to want help. There is only so much you can do.

And yes, stunting can occur by small tank size. It has been proven. I'm sure more people will respond to this so I will leave that alone.

And just because you think you know something, doesn't mean you are right 100% of the time. This goes for everybody. Here is an example of how I feel your last post was like....I posted here and a Facebook group for a problem with little tiny planaria that I got from some floating plants. People here tried to help. This isn't about this forum. But one person on the facebook group said they were only detritus worms, they won't harm anything. Well...a lot of fish died(from these and maybe something else) but so did a nerite snail. These things attacked my snails, causing one to die. This person just absolutely wouldn't believe me even though I saw it with my own eyes.

Anyway, don't be like that guy. Nobody likes people like that. I've gotten great advice on here from people. I have hard water but I've gotten advice from great people on how to do a tetra tank, in my water. Most people would bash me about having tetras in anything over 7.0 ph. Mine is 8.2. But no bashing here.
 
I dunno Colin, I've been on this forum awhile and I don't think I've ever seen a poster treated harshly for having too small a tank, Oh I've seen it mentioned and sometimes rightly so. It's a fair message to spread. I cringe every time I go into a pet store and see Betas in those tiny cup bowls. Or any large tropical fish in a relatively small tank for display. What message does that send to the lay consumer?

Many people enter the hobby without regard to the requirements or the consequences. It's not intentional....just just that you don't know what you know till you learn it. And sometimes, it's knowledge gained the hard way.

A small tank can be more problematic as it simply takes less time for bad things to happen. a Fish too large or too many can accelerate the decline.
So if someone happens along with a small tank and large or too many fish, I'll tell them what I think...for their own good and for the good of this fish they may be torturing. I won't be cruel, but they need to learn.
 
I love a good debate but I'm too lazy to address all the points made so I will pick and choose.

The pathogens must be in the tank for the fish to become infected with them.

There is no such thing as a sterile aquarium setting. If I were to stop doing water changes and only feed my currently healthy and disease free tank, problems with internal parasites, ich, flukes, as well as bacterial and fungal problems would certainly arise. Many fish diseases are always present in an aquarium, but only in small numbers that pose no danger to the fish. Disease breaks out only when conditions are less than ideal for the fish, leading to stress and resulting in compromised immune systems.

If someone's aquarium appears is too small for the fish they are keeping, you can SUGGEST their fish would probably do better in larger quarters. But try to be tactful about it and only mention it after you have answered or helped with the original problem.

If disease is a result of overcrowding and/or too small a tank, the OP is likely to have the same reoccurring issue. If they treat the disease but not the cause of that disease it will come back in time. If I had someone to tell me "your little 5gal is too small for a trio of common goldfish" or "that green spotted puffer will grow massive and eat your other fish" I probably wouldn't of bought them. 12 year old me killed so many fish because of a tiny tank, if I had a verbal slap on the wrist I would bet all the past fish I killed wouldn't have had such a tragic end.

Sometimes even adults need to be told "no, you can't do that". I honestly get a little tired of having to dance around and trying to be tactful to avoid upsetting someone who is clearly not getting the point.

On another note, if people would take the time to educate themselves on the animals they are currently keeping they would find out for themselves how terrible the conditions are for their aquatic pets. The good Lord knows how many hours I've spent researching the fish I keep and the changes I've made to keep them healthy. I understand that everyone has to start somewhere so why not give them a little verbal smack on the behind to get them going.
 
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Well said. A major difference is that when you are a breeder you understand the requirements and daily 50 - 75% water changes are just part of the job. Sadly many new hobbyists are led to believe that a monthly 10% change is all it takes (and how many remember every month?). Yes bad stuff does get introduced. Last week I treated with levamisole for just such an occurence. That was the first time I have added meds to any tank or pond since 2004. Its kind of hard to put that down to just dumb luck.

Education is important, and the animal welfare charities don't concern themselves with fish. Very few people (one can only hope) would try to keep 3 large dogs in a 1 bedroom apartment while they are at work all week because "there is plenty of space for them to sleep".

Personally I think it is commendable how many newcomers to the site do go out and get larger tanks (or return fish) once they realise what the facts are. Sure a disciplined fish keeper (experience has nothing to do with it) could probably keep 2 goldfish in a 5G. Way to much work for me and I can't commit to that number of water changes so I won't be trying. And when someone says "help the 2 goldfish in my 5G are sick" my responsibility should go beyond telling them what meds to buy.
 
A lot of people that come onto this forum have small aquariums, and they do so for various reasons. They could have financial restraints, lack of room, move a lot, or just don't want a big tank and don't want to spend a $1000 on a new hobby they might not stay with. Whatever the reason, it is up to them.

I have noticed that when people come on here asking for help with fish health issues, some of them get told (often in pretty abrupt terms) that their tanks are too small and that is why their fish are dying. This is often rubbish as the fish are usually dying from a disease, not a small tank. And whilst some of you will say the disease is caused by the stress that comes from living in a small tank, that is also rubbish. The diseases get brought into the tank by fish, plants, snails, water from a shop, etc, and the fish become infected with the pathogen. This can occur in a 20 litre tank or a 2000 litre tank.

I will agree that small tanks are more prone to fluctuating water chemistry and are more likely to have problems with ammonia & nitrite due to their smaller water volume. However, many people do cycle the tank without fish in, and those who don't can do big regular water changes to dilute the nutrient/ chemical build up. Having said this, if there are no disease organisms in the aquarium, the fish will not develop a disease simply from being in a small tank. The pathogens must be in the tank for the fish to become infected with them.

----------------------
Being told their tank is too small can be quite unpleasant for the person asking for help. Many people that are new to fish keeping come here looking for help and it is up to the more experienced fish keepers to OFFER ADVICE ABOUT THE PROBLEM. If someone's aquarium appears is too small for the fish they are keeping, you can SUGGEST their fish would probably do better in larger quarters. But try to be tactful about it and only mention it after you have answered or helped with the original problem.

People that are losing fish are stressed out enough knowing their fish are dying. If they are new to fishkeeping and have no idea what is causing the problem, that makes it worse. Do not add to their stress by having a go at them because their tank might be (in your opinion) too small.

In a perfect world you would not be able to buy a fish tank less than 6ft long, nothing would get sick or die and wild fishes would not be endangered. We don't live in a perfect world. People don't always get good advice when they buy a fish or a fish tank from a shop, and we should not have a go at them simply because they did.

Please, try not to have a go at new people who happen to have a small aquarium. Offer helpful advice and be tactful. Put yourself in their shoes for a moment and think about how you would feel if you had just bought a tank from a pet/ aquarium store and you go home, set it up and start losing fish. Then you find a forum that appears nice and friendly and helpful, and someone says "your tank is too small, that's why your fish are dying". If you didn't know any better, how would you feel?
Well said Colin_T

That's exactly how I felt.

Thankyou for your advise.

Oh and my little guppies are all still happy which I find with animals is a best sign.

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Guides seem to be consistent.......

Or are they all wrong?

4 gallons of water for 3 guppies
6 gallons of water for 6 guppies
9 gallons of water for 9 guppies and so on.

http://www.theaquariumguide.com/articles/how-to-care-for-guppies

US gallon 3.7 x 7 guppies = 25.9L

My little tank is not so small after all, especially when my guppies are all under 9 months old.

Weekly water changes with a quick clean takes 10 minutes not really a problem.




Sent from my SM-N9005 using Tapatalk
 
Guides seem to be consistent.......

Or are they all wrong?

4 gallons of water for 3 guppies
6 gallons of water for 6 guppies
9 gallons of water for 9 guppies and so on.

http://www.theaquariumguide.com/articles/how-to-care-for-guppies

US gallon 3.7 x 7 guppies = 25.9L

My little tank is not so small after all, especially when my guppies are all under 9 months old.

Weekly water changes with a quick clean takes 10 minutes not really a problem.

I went to that site and had a look. The information is totally inaccurate. Three guppies should not be in 4 gallons of water; three guppies in a 10 gallon [= 38 liters] tank is minimal. You can have a few more, but nothing smaller than a 10 gallon should be considered suitable for these fish, assuming that one is going to want more than just one. And this also assumes males only; females and males means batches of fry and not all will get eaten so they need to be removed as they grow.

A 10 gallon tank is really best suited for nano type fish (which guppies are not, attaining 2 to 2.5 inches (6 cm). Nano fish are species like those in Boraras (dwarf rasbora species). Or a single male betta. Pygmy cories. Endler livebearers. And such.

Oh and my little guppies are all still happy which I find with animals is a best sign.
Unless one is able to somehow get inside the mind and the body of the fish, you cannot know what effect the environment is having. That is why we follow the advice of biologists and ichthyologists who spend years studying fish physiology and metabolism. "Happy" is a subjective term; if the fish is behaving normally, and the internal processes are functioning properly, it is likely in good health and "happy" so to speak.
 
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I went to that site and had a look. The information is totally inaccurate. Three guppies should not be in 4 gallons of water; three guppies in a 10 gallon [= 38 liters] tank is minimal. You can have a few more, but nothing smaller than a 10 gallon should be considered suitable for these fish, assuming that one is going to want more than just one. And this also assumes males only; females and males means batches of fry and not all will get eaten so they need to be removed as they grow.

A 10 gallon tank is really best suited for nano type fish (which guppies are not, attaining 2 to 2.5 inches (6 cm). Nano fish are species like those in Boraras (dwarf rasbora species). Or a single male betta. Pygmy cories. Endler livebearers. And such.

Oh and my little guppies are all still happy which I find with animals is a best sign.
Unless one is able to somehow get inside the mind and the body of the fish, you cannot know what effect the environment is having. That is why we follow the advice of biologists and ichthyologists who spend years studying fish physiology and metabolism. "Happy" is a subjective term; if the fish is behaving normally, and the internal processes are functioning properly, it is likely in good health and "happy" so to speak.
Thankyou, can you therefore please send me a link to your resources?


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I went to that site and had a look. The information is totally inaccurate. Three guppies should not be in 4 gallons of water; three guppies in a 10 gallon [= 38 liters] tank is minimal. You can have a few more, but nothing smaller than a 10 gallon should be considered suitable for these fish, assuming that one is going to want more than just one. And this also assumes males only; females and males means batches of fry and not all will get eaten so they need to be removed as they grow.

A 10 gallon tank is really best suited for nano type fish (which guppies are not, attaining 2 to 2.5 inches (6 cm). Nano fish are species like those in Boraras (dwarf rasbora species). Or a single male betta. Pygmy cories. Endler livebearers. And such.

Oh and my little guppies are all still happy which I find with animals is a best sign.
Unless one is able to somehow get inside the mind and the body of the fish, you cannot know what effect the environment is having. That is why we follow the advice of biologists and ichthyologists who spend years studying fish physiology and metabolism. "Happy" is a subjective term; if the fish is behaving normally, and the internal processes are functioning properly, it is likely in good health and "happy" so to speak.
And another same ratio..............

http://www.guppyfishtank.com/perfect-tank-size-for-guppies/


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I will explain the thinking as best as I can. Let me begin by saying there is no "rule" that will work to determine how many gallons per fish or vice versa. There is simply so much more to this.

The ratio of fish to water volume in nature is miniscule; i.e., there are very few fish per volume of water. Obviously we cannot replicate that in most situations. But when considering tank size and fish numbers there are two primary aspects: one is the physical space a given species needs to function normally, and the other is the water quality.

Active swimming fish need more space than sedate non-active fish. They need the space to be active, but they also have more of an impact on the water quality. Sedate fish will respirate more slowly, and usually eat less, producing less waste, so there is less of an impact biologically than there would be for very active fish of the same size. Active fish are often releasing more pheromones and allomones as well, further impacting water quality. Fish in nature do not remain in the same water from respiration to respiration; or, to put it another way, the water a fish takes in and passes through the gills in respiration will be "fresh" each time the fish does this. In any aquarium, eventually the water is the same water each time, and this impacts the fish. This is why it is almost always better to have larger tanks, and why we do significant water changes regularly. Minimum tank sizes are unfortunate, but we need to have them so the fish will have a better chance of being healthy. But it is good to keep in mind that most of the time, exceeding the minimum space will always be better for the fish.

So, if a given species is said to need a 24-inch 20 gallon tank, in most cases it will be better in a 30-inch 29 gallon tank. You might also be able to have more of them, and this is critical with species we term shoaling or schooling; here again, minimum numbers are just that, minimum, and having more is almost always going to improve the fish's health because we are getting closer to what it "expects." Think of the betta in a cup of water in so many stores; obviously the fish will survive, but it will not be in good health; survive and thrive are very different things, and responsible aquarists must always aim for the latter, providing what the fish expects/needs/requires so it will not just live (survive) but thrive. Anything less is frankly inhumane.

This brings me to your request for sources. These days, anyone with some money can set up a web site and promote themselves as "experts." As we all know, there is a wide range of different advice on the same topic depending which site you read. I have been carrying out research on fish species and habitats for years, and I have learned two things: first, the only really reliable sources are those where biologists, microbiologists and ichthyologists contribute or at the very least scrutinize the data, and second, it is interesting (but not really surprising) that these sites tend to agree on the data/information. Once you find such a site, stay with it.

Many if not most of us on this forum use Seriously Fish as our prime source. If you are into catfish, Planet Catfish and specialized sites like Corydoras World are reliable. Loaches Online is reliable for information on the loach family. And there are others. But SF will usually provide all you need, and then some for added interest. I know, either by reputation or personally, the individuals who run the sites I've mentioned, and they are trained biologists and ichthyologists.

There are several very experienced members here on TFF too. But the really good thing about this forum is what we term peer review; anything one of us posts is read by others, and errors, different opinions, or agreement will raise the reliability aspect of the advice. As you joined earlier this week...welcome to TFF. Never be hesitant of asking for advice, clarification, help...whatever.

Byron.
 
Big fish small tank.


Its also about quality of life.
 
Active swimming fish need more space than sedate non-active fish. They need the space to be active, but they also have more of an impact on the water quality. Sedate fish will respirate more slowly, and usually eat less, producing less waste, so there is less of an impact biologically than there would be for very active fish of the same size. Active fish are often releasing more pheromones and allomones as well, further impacting water quality. Fish in nature do not remain in the same water from respiration to respiration; or, to put it another way, the water a fish takes in and passes through the gills in respiration will be "fresh" each time the fish does this. In any aquarium, eventually the water is the same water each time, and this impacts the fish. This is why it is almost always better to have larger tanks, and why we do significant water changes regularly. Minimum tank sizes are unfortunate, but we need to have them so the fish will have a better chance of being healthy. But it is good to keep in mind that most of the time, exceeding the minimum space will always be better for the fish.
A filter and surface turbulence will compensate for any breathing sedate or active fishes do.

Whilst guppies might move around a lot, they do not need a lot of swimming space unlike rainbowfishes and Galaxias. And the fish in shops have been domesticated for over 50years. They are not wild fish that travel kilometres up and down rivers looking for food. They are domestic guppies that have probably never seen sunlight or been in a water body with more than 500litres. The exception to this might be a sewerage pond in Asia where they might have been born in.

All fishes including ambush predators (sedate fish), are opportunistic feeders and will eat as much food as they can whenever it is available. In fact ambush predators usually have a bigger impact on water quality and sudden ammonia spikes because they eat large prey/ meals, and this means a lot of food going into the tank suddenly.

The most common pheromones released by fish are breeding pheromones, and are harmless. They also encourage other fish to breed so are not an issue in an aquarium. And your post was aimed towards someone with guppies in their tank. Guppies don't need or care about sex pheromones, they are randy little buggers that can't keep it in their pants.

Growth inhibiting hormones are released by baby fish in an attempt to reduce the growth of other fry around them. Adult fishes do not produce these hormones and they can be diluted quite easily with water changes.

Unless wild fish manage to remain in a large deep waterbody like a river, they do end up in small confined puddles of water and have the same dirty water flowing over their gills. Many rivers dry up to some extent during the dry season and they leave pools, ponds, billabongs, lagoons behind with the fish in. The water slowly evaporates out of these pools and the fishes living in them have to deal with less oxygen, warmer water, more waste products, and even algae & fine sediment flowing over their gills. And if there are predators in the area (water birds, crocodiles, mammals) these fish then have to contend with being eaten while they struggle to survive in the ever shrinking water body.
Yes in a nice clean river the fish have clean water. But how many rivers have rubbish along the banks, chemical runoff going into them, algae and other man made and natural pollutants? Unless you get into the pristine reaches of the wilderness, you will probably find most rivers are not that clean. And neither is the ocean.

Yes it is better to have a nice large tank for fish, but as mentioned in my original post, not everyone has the finances to afford a big tank, nor does everyone have room for a big tank. And not everyone wants a big tank. If the fish are breeding and not coming down with diseases all the time, then they are obviously reasonably healthy.
 

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