What is a tropical aquarium?

GaryE

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At a first glance, this one looks easy. It's a warm water tank!

But what's warm?

A tropical fish is defined by where it comes from. What the temperature is there depends on trees, sunlight and water flow. A tropical stream in Central Africa can be 22c/71f, if the forest canopy hasn't been logged away, and the water flows from hills. The area around the water can be quite dark even at noon, as no sunlight gets through.
In a wide river, it will be warmer, getting up to 25/77 or higher in many places. Discus come from very warm water.
A pool or small lake in a grasslands will get the full force of the sun, and fish like rams are heat hogs because of that. They'll live in a tank at 27/81, and can go higher.
A fish from a brook deep in a rainforest can live in anything from 18c/64f to 25/77, depending on geography, tree cover the flatness of the land, etc.

We have a tendency to crank the heat in our tanks. It seems like every decade, hobbyists go up a degree. I read of people with neons at 27/81. Why???? A quick look at any data on their natural environments will tell you to stop wasting energy and money, and to stop shortening their lifespans with excessive warmth.
Aquarium water temperature can be very inconvenient if you want to keep rams with neons. Somebody has to be made to suffer. You can avoid that by searching info on the natural habitats of your fish (Seriously Fish and Fishbase are good starting points) before you buy them. Remember, these are cold blooded animals, unlike our warm blooded selves.

Nothing stops you from keeping fish at the wrong temperature, if you aren't concerned about being unkind to them. Too warm, and their lives are shortened and they can waste away. Ditto for too cool. Many species have digestive enzymes that only work properly in a certain temperature range. That's food for thought. Put a little bit into learning about your fish before you buy( you can often google info on your phone if you see something new to you at the store) and you'll get a lot out of it. So will your fish - they'll be on the road to a suitable environment.
 
It seems like every decade, hobbyists go up a degree.
Global warming could be a factor.

The Ram and Neon issue is a good example. Sadly many hobbyist do not realise they are shortening a fish life and adding stress to the fish by being at 80 F, obviously for some fish this is ideal. Of course, heatwaves are excluded as we know many of the fish who prefer 75 F can be comfortable without health risks at 80 F for a while or higher (I think), but not on going.

The vast majority of corydoras is the same example of the neon/ram debate.
 
At a first glance, this one looks easy. It's a warm water tank!

But what's warm?

A tropical fish is defined by where it comes from. What the temperature is there depends on trees, sunlight and water flow. A tropical stream in Central Africa can be 22c/71f, if the forest canopy hasn't been logged away, and the water flows from hills. The area around the water can be quite dark even at noon, as no sunlight gets through.
In a wide river, it will be warmer, getting up to 25/77 or higher in many places. Discus come from very warm water.
A pool or small lake in a grasslands will get the full force of the sun, and fish like rams are heat hogs because of that. They'll live in a tank at 27/81, and can go higher.
A fish from a brook deep in a rainforest can live in anything from 18c/64f to 25/77, depending on geography, tree cover the flatness of the land, etc.

We have a tendency to crank the heat in our tanks. It seems like every decade, hobbyists go up a degree. I read of people with neons at 27/81. Why???? A quick look at any data on their natural environments will tell you to stop wasting energy and money, and to stop shortening their lifespans with excessive warmth.
Aquarium water temperature can be very inconvenient if you want to keep rams with neons. Somebody has to be made to suffer. You can avoid that by searching info on the natural habitats of your fish (Seriously Fish and Fishbase are good starting points) before you buy them. Remember, these are cold blooded animals, unlike our warm blooded selves.

Nothing stops you from keeping fish at the wrong temperature, if you aren't concerned about being unkind to them. Too warm, and their lives are shortened and they can waste away. Ditto for too cool. Many species have digestive enzymes that only work properly in a certain temperature range. That's food for thought. Put a little bit into learning about your fish before you buy( you can often google info on your phone if you see something new to you at the store) and you'll get a lot out of it. So will your fish - they'll be on the road to a suitable environment.
I totally agree with this. It's the same by saying: Is a fish a tropical or subtropical fish eventhough it's coming from a tropical country. It's the location within that country that makes a fish tropical or subtropical. The location determines whether we're dealing with tropical or subtropical fish by the factors prevailing there...
 
I think a lot of it has to do with the indiscriminate "tropical" branding. People hear that word and simply assume hot. I see something somewhat similar in the reptile/amphibian hobby too, on occasion. I now have two Litoria caerulea (dumpy tree frogs). They are technically tropical animals—native to Queensland (AUS) and parts of Indonesia—and are branded as such. Certainly, it's warm there, but their native habitat is heavily forested and they spend most of the daytime sleeping in the shade. As a result, I've seen people express some surprise when they're told they should keep these frogs no hotter than about 82F/28C, and that's only in their basking zone, and only during the daytime. Their night temps should dip down to about 65F/18C.

Anyway, I wonder if there could also be some influence from the disease/healthcare side of the aquarium hobby. I see a lot of non-expert advice marketed to beginners/casual keepers which involves raising the temperature of the tank to "cure" all sorts of diseases. It almost seems, at times, that the advice ends up being to keep the temps up at all times to "prevent" disease. Same thing with salt, but that's a whole other discussion to have...
 
A lot of skilled rainbow keepers keep their fish cooler, and only go warm for breeding. It can help slow bacterial problems like Mycobacter.

I think a lot of it has to do with the old idea that fish will adapt to whatever, as they are just aquarium fish. A few generations of farm breeding is said to overturn ancient adaptations. Hardwater, softwater, temperature, none of this matters in the fish as ornaments view that still flourishes in our hobby. I've been accused of lying when I said I had entire shoals of tetras, like cardinals, living 5, 7 or 9 years. I'm told they are really old at 3.
 
A lot of skilled rainbow keepers keep their fish cooler, and only go warm for breeding. It can help slow bacterial problems like Mycobacter.

I think a lot of it has to do with the old idea that fish will adapt to whatever, as they are just aquarium fish. A few generations of farm breeding is said to overturn ancient adaptations. Hardwater, softwater, temperature, none of this matters in the fish as ornaments view that still flourishes in our hobby. I've been accused of lying when I said I had entire shoals of tetras, like cardinals, living 5, 7 or 9 years. I'm told they are really old at 3.
I never got this idea that a few generations of selective breeding will overcome millions of years of evolution either.
 
Nothing stops you from keeping fish at the wrong temperature, if you aren't concerned about being unkind to them. Too warm, and their lives are shortened and they can waste away. Ditto for too cool. Many species have digestive enzymes that only work properly in a certain temperature range. That's food for thought. Put a little bit into learning about your fish before you buy( you can often google info on your phone if you see something new to you at the store) and you'll get a lot out of it. So will your fish - they'll be on the road to a suitable environment.
I have a rule that I strictly follow in fish keeping. Never buy an animal on impulse. I spend weeks if not months researching the fish. I want to know its water parameters, school or shoal size and tank size, just for starters. Then I need to know if it's compatible with the other fish I intend to keep it with. Then I find out about its care and feeding. How can I provide it with the best habitat. And since I don't want them to just survive, what kind of enrichment can I give them so they thrive.
To me, that's a minimum for keeping fish. Most people grow up with dogs and cats. So they at least know the basics of caring for one of them. Fish are a much different story and this is a research intensive hobby.
So when I go to a fish store, I know what I'm buying before I ever step through the door. I call ahead to make sure they have it in stock. And if there's a mistake, then no substitutes. I'll buy plants, food or equipment in the spur of the moment. But not an animal. I'm not an animal rights activist or anything. But I feel like if I assume responsibility for a living breathing creature that can't care for itself, then I owe it the best care I can give it.
 
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this is a research intensive hobby.
So when I go to a fish store, I know what I'm buying before I ever step through the door. I call ahead to make sure they have it in stock. And if there's a mistake, then no substitutes. I'll buy plants, food or equipment spur if the moment. But not an animal. I'm not an animal rights activist or anything. But I feel like if I assume responsibility for a living breathing creature that can't care for itself, then I owe it the best care I can give it.
I couldn't agree more.

I once had a guy get really angry when I talked about our need as fishkeepers to learn about and adapt to the natural histories of our fish. He told me adaptation and evolution were lies. Then he told me fish changed when they were bred on farms so they didn't need any special set ups. They changed because if they didn't, they wouldn't be able to survive in tanks.

We are a strange bunch in this hobby.
 
Ignorance always wins, when left to its own devices. I still see the same ignorance now as I did fifty years ago. It's much easier now to find out about the environment of almost any tropical fish, but the ignorance that makes people believe that if you work in a shop you must know about what you're selling still prevails for the majority. Also the lack of consideration given by our species to animal wellbeing in general is still shockingly poor, on average.
I see it changing excruciatingly slowly, and I think there will always be shop people who only care about the cash register... and there'll always be fishkeepers happy to remain ignorant, because they're only fish.
 
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A lot of data in places like seriously fish is incorrect and points to warmer temps; also certain species (such as many dwarf cichild) require proper temp for even distribution of sexes when breeding. Of course in the wild they solve this issue with the dominant female taking the upper region (more males) and the smaller females taking lower regions (more females).
 
Anyway, I wonder if there could also be some influence from the disease/healthcare side of the aquarium hobby. I see a lot of non-expert advice marketed to beginners/casual keepers which involves raising the temperature of the tank to "cure" all sorts of disease
The internet is full of incorrect info. One should really be careful whether info is correct or not. But also the commercial trade is guilty of spreading wrong information. And it starts with wholesalers.
I've been accused of lying when I said I had entire shoals of tetras, like cardinals, living 5, 7 or 9 years.
If someone reads up that the average or max age is 3 years for instance, and somebody else claims that they can get older, that person will almost be shouted at. For they believe what they've found of information on the net is the only correct information. That my friend, will always be the situation no matter how frustrating it may sound...
They changed because if they didn't, they wouldn't be able to survive in tanks.
Yes, with a lot of fish species when bred in captivity for generations, their tolerance for certain water parameters can change. But that doesn't mean that this will go for every fish species. And serious aquarists try to copy the water parameters in free nature the best way they can. If this person claims differently, then he's lacking knowledge. So, good that you told him differently.
I see it changing excruciatingly slowly, and I think there will always be shop people who only care about the cash register... and there'll always be fishkeepers happy to remain ignorant, because they're only fish.
Those people aren't true aquarists, by all means...
 
I couldn't agree more.

I once had a guy get really angry when I talked about our need as fishkeepers to learn about and adapt to the natural histories of our fish. He told me adaptation and evolution were lies. Then he told me fish changed when they were bred on farms so they didn't need any special set ups. They changed because if they didn't, they wouldn't be able to survive in tanks.

We are a strange bunch in this hobby.
People in this hobby can have a tendency to engage in confirmation bias. They only want to believe what's convenient for them.
 
People in this hobby? People in everything, I'm afraid. Convenience is very tempting.
Yeah but this should be science based. Instead we get people ignoring the biological needs of a fish because of their own wants. "I'm going to keep hard water and soft water fish together because that's what I want to do and I'll rationalize it after the fact." Or people who don't do water changes who rationalize their lazy husbandry with pseudo science.
 

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