Why can't Goldfishes be put with Tropical fishes?

[Zodiac007]

I currently have 3 goldfish in a 10 gallon. 1 as a comet goldfish, its very beautiful, with long fins. I've had it for over 3 years and its still only 3 or 4 inches. The other 2 are common goldfish I think, 1 is about 3 inches, and 1 is about 2 inches. Other than that, they are very healthy and happy. I've had them for over 3 years now.

I'm going to get a 50 gallon long aquarium soon. I've decided on a planted tank.

Fishes will be : 10 Harlequin rasboras, 8 cardinal tetras, 1 britlenose pleco, and 3 oto catfish.

I'm thinking of putting my 3 goldfishes in the tank too. Since I think their growth has been stunted, they probably wont grow much anymore and stay at around 4 or 5 inches. Since they are so small, I don't see a risk that they will eat any of the tropical fishes, since their mouth is so small too. And actually I've had these with neon tetras before and it was fine.

Also, about the coldwater thing. I think they've adapted to warm water too because I've had them for over 3 years in a 10 gallon thats around 20- 25 degrees celsius and they are still healthy, maybe not very happy, but still healthy.

So if they really have adapted to the warm water and their growth really have stunted, will it be alright to add them to the 50 gallon? because now I don't see any problems.

Thank you.

[AABatteries]

They may or may not grow to full size. If so, 50g is just above the minimum for 3 goldfish. I'd have the 3 goldies, a bristlenose pleco, and a blue or gold gourami. Or any gourami, just not a giant gourami.

[Deleted User]

Goldfish are cold water fish. Tropical fish need a heated tank. Goldfish won't like the temperature your tropicals will need .:ssmile:

[Zodiac007]

Also would anyone know why my comet goldfish has a long body shape. I searched on google for comet goldfishes, and they are all fat and rounded. Mines is a long shape, like a shark's body shape. And with a long fork tail.

[Lady Hobbs]

A 10 gallon is much to small for goldfish but guess you know that. If they are still small after all this time, their growth has probably been stunted by that small tank.

[Mvjnz]

Goldfish are not coldwater, they like cold as well as warm water. This is called eurythermal (http://www.practicalfishkeeping.co.uk/pfk/pages/glossary.php?entry_name=Eurythermal).

So it will be fine with tropical fish as far as temp goes, but I don't recommend the combo because goldfish are very messy so they need strong filtration, and they get big enough to see smaller fish as food.

[MrJim]

Also would anyone know why my comet goldfish has a long body shape. I searched on google for comet goldfishes, and they are all fat and rounded. Mines is a long shape, like a shark's body shape. And with a long fork tail.

The comet sounds like mine (see pic at gallery link in sig)~I started with a 2.5gal and moved to a 10 last year; she lives with the tropicals listed in my sig at about 77 degrees and is doing fine other than I think she is stunted now...plan on moving her to a pond this spring.

They seem very adaptable and suppose since she's been in 77 degree water for a couple years that she could continue with her buddies, but it really isn't the best set up-excessive bioload, have to keep up with water changes to keep ammonia at bay. If you want to try it out in the big tank then maybe just give more room but don't add a lot of other fish. I would not recommend the pleco-word is they'll latch on to the side of a goldie just like I saw an algae eater latch onto mine a couple times..maybe go with one of those snakey loaches or something instead? I don't know if the otos would latch on or not, none of mine never tried that I saw.

On the tetras, mine tend to hover toward the bottom. I think not only the danios but also the goldie intimidates them. Neons are probably similar to cardinals, and they seem to be very peaceful & gentle fish, and the goldie being so much larger and "in charge" seems to keep them in the corner when they ought to be swimming about more. Sure, mine are healthy and growing, but I don't think they are "happy".

These folks here give lots of great advice, wish I'd been here way sooner. Aquarists are more than just people keeping fish alive, but providing the ideal environment for success~I've screwed up so much figuring I knew best what to do with the proper research...lost some prized fish, yeah the cash value was less the $5 (a goldie, a cory, an oto) but still they died unnecessarily and at my fault for improper fishkeeping. The education continues..

[tanks4thememories]

Also would anyone know why my comet goldfish has a long body shape. I searched on google for comet goldfishes, and they are all fat and rounded. Mines is a long shape, like a shark's body shape. And with a long fork tail.

Comets are so over farmed for the novelty and feeder industry you could easily have one that is genetically different than most others, no worries its just different not bad or good.

As to putting them in the same tank goldfish are really messy they generate a lot of bio load on a tank so 1 goldfish is like having 2 tropical ones this cuts down the amount of total fish you can have in a tank.

Temperature wise they like colder water so its not a good idea to keep them in the same temperate zone.

On a personal note I feed minnows and goldfish to my fish and every once and a while one is smart enough to live in the tank for a few weeks without being eaten. I notice they handle the temp just fine the thing is if I were keeping gold fish as a pet not as food and wanted them to be happy then that wouldn't be the temperature to keep them at.

In short there are things you can get away with and there are things you should do because it is good for your pets. If your goal is keeping gold fish then you owe it to them to keep them at the correct temperature.

[MrJim]

Comets are so over farmed for the novelty and feeder industry you could easily have one that is genetically different than most others, no worries its just different not bad or good.

As to putting them in the same tank goldfish are really messy they generate a lot of bio load on a tank so 1 goldfish is like having 2 tropical ones this cuts down the amount of total fish you can have in a tank.

Temperature wise they like colder water so its not a good idea to keep them in the same temperate zone.

On a personal note I feed minnows and goldfish to my fish and every once and a while one is smart enough to live in the tank for a few weeks without being eaten. I notice they handle the temp just fine the thing is if I were keeping gold fish as a pet not as food and wanted them to be happy then that wouldn't be the temperature to keep them at.

In short there are things you can get away with and there are things you should do because it is good for your pets. If your goal is keeping gold fish then you owe it to them to keep them at the correct temperature.

Just wonderin'~do you reward the survivors with amnesty?:hmm3grin2orange:

[tanks4thememories]

Just wonderin'~do you reward the survivors with amnesty?:hmm3grin2orange:

LOL actually somtimes I do. But it rarely lasts long if I took it back to the LFS they would just sell it as a feeder to somone else. so I put them back in the feeder holding tank and they get a chance not to be picked for next feeding...lol Unfortunately That is as good as it gets.

[MrJim]

LOL actually somtimes I do. But it rarely lasts long if I took it back to the LFS they would just sell it as a feeder to somone else. so I put them back in the feeder holding tank and they get a chance not to be picked for next feeding...lol Unfortunately That is as good as it gets.

Temporary stay of execution~another day to eat and play...guess that's not so bad..:goldfish:

[tanks4thememories]

Temporary stay of execution~another day to eat and play...guess that's not so bad..:goldfish:

heheh yeah. If I ever get back to having a large feeder tank like I used to have then there would also be a significant chance they could never be picked due to the tank always being full of new victims who don't know how to avoid the net...lol The most interesting feeder fish I ever used was giant danios that I had used to cycle a tank they were so fast and had grown so large after about 2 months of them not getting eaten I took the survivors to the LFS and got a credit...lol

[SusieQ]

i have 5 goldfish with other tropical fish in a 75 gallon tank and they are doing great. the temp is about 72 degrees. they give off ammonia so you are really not supposed to have them in with tropical fish but i didn't know this when i got them. they are big, about 4 inches i guess.

[tanks4thememories]

i have 5 goldfish with other tropical fish in a 75 gallon tank and they are doing great. the temp is about 72 degrees. they give off ammonia so you are really not supposed to have them in with tropical fish but i didn't know this when i got them. they are big, about 4 inches i guess.

Yup people do it. Its just that you know the goldfish arent really happy at that temp. As to them giving off ammonia all fish do that its just gold fish eat a lot more than other fish so they give off more.

[Fishguy2727]

Per weight goldfish do not give off any more waste than other fish, they just have more weight on them than many other fish.

The temp is fine, goldfish are native to subtropical to tropical areas, but they are naturalized to the most tropical waters on the planet, they are fine. Really fancy goldfish breeds may not do as well for a very extended period of time in very high temps (in the mid 80s).

They do truly thrive in higher temps. They live and breed in places like Vietnam, the Amazon River system, the Middle East, small ponds in Florida, etc.

Are they all long-bodied or are the other two round-bodied double-tailed?

If they are all long-bodied they would need that whole tank to themselves. If they are round-bodied you could fit one or two more in there (depending on how big these three get).

Bristlenose plecos won't bother goldfish, generally.

Otocinclus are actually sub-tropical as well, ideally in the lower 70s.

I think the best thing to do would be to devote the 50 to the goldfish and use the ten as a small, well planted community tank. You could do cardinals or harlequin rasboras, plus a small cleanup crew.

[tanks4thememories]

Per weight goldfish do not give off any more waste than other fish, they just have more weight on them than many other fish.

The temp is fine, goldfish are native to subtropical to tropical areas, but they are naturalized to the most tropical waters on the planet, they are fine. Really fancy goldfish breeds may not do as well for a very extended period of time in very high temps (in the mid 80s).

They do truly thrive in higher temps. They live and breed in places like Vietnam, the Amazon River system, the Middle East, small ponds in Florida, etc.

Are they all long-bodied or are the other two round-bodied double-tailed?

If they are all long-bodied they would need that whole tank to themselves. If they are round-bodied you could fit one or two more in there (depending on how big these three get).

Bristlenose plecos won't bother goldfish, generally.

Otocinclus are actually sub-tropical as well, ideally in the lower 70s.

I think the best thing to do would be to devote the 50 to the goldfish and use the ten as a small, well planted community tank. You could do cardinals or harlequin rasboras, plus a small cleanup crew.

Goldfish produce more waste than tropical fish

Because goldfish are temperate animals, they can withstand a wide range of temperatures. In a natural pond, or a water garden large enough, goldfish may even winter over when the water freezes at the surface. In the aquarium-it's best to maintain them at 68 to 76 degrees F. Because of their metabolic demands, the cooler water is best for their survival.

"Goldfish are natural born pigs. They are messy. And they eat a lot. Thus creating the biggest obstacle for many goldfish keepers-the water quality. Like most fish, goldfish prefer to live in clean water. They can tolerate a wide range of pH, but prefer neutral to slightly basic water. They do not do well in any aquarium with ammonia or nitrite present. Since they can easily produce huge quantities of wastes, and ammonia, they should be kept in well-filtered aquariums. That's right-filtered aquariums. Problem is most people try them in a very small bowl first." (http://www.aquariumhobbyist.com/articles/Goldfish.html)

Goldfish are thick-bodied fish who eat a lot and produce a LOT of waste. The bowl quickly becomes polluted with the fish choking on their own excreta. If that doesn’t somehow seem cruel to you, imagine buying a Saint Bernard puppy and keeping it in a two foot by two foot crate, never letting him out, and only cleaning his messes once a month or so. If you think that bowl smells bad above water, imagine trying to breathe below the surface – something like living in your own toiletbowl. Goldfish need a lot of water. Babies require TEN gallons of water per fish and adults 30 gallons each."]"Goldfish are thick-bodied fish who eat a lot and produce a LOT of waste. The bowl quickly becomes polluted with the fish choking on their own excreta. If that doesn’t somehow seem cruel to you, imagine buying a Saint Bernard puppy and keeping it in a two foot by two foot crate, never letting him out, and only cleaning his messes once a month or so. If you think that bowl smells bad above water, imagine trying to breathe below the surface – something like living in your own toiletbowl.

Goldfish need a lot of water. Babies require TEN gallons of water per fish and adults 30 gallons each.
(http://www.bihartimes.com/Maneka/crueltytogoldfish.html)

Goldfish need more oxygen than tropical fish

"As temperature rises, the ability of water to carry dissolved oxygen decreases. At the same time, as the water heats up, the goldfish's metabolism speeds up and more oxygen is required. This creates the following conundrum: The warmer the water - the less oxygen ; the warmer the water - the more oxygen goldfish need. " (http://www.kokosgoldfish.com/TankAerationInSummer.html)

That isn't to say that people don't bend these rules and do it anyway but ignoring the facts doesn't make them disappear. There are many circumstances where an animal may survive in less than ideal conditions for that animal but as somone here on this forum once said and I love it "there is a difference between survive and thrive". It isnt always noticable by how active a fish is either. Personally if I have a pet I want it to be in an ideal enviornment for the pet or I should choose a different pet.

[klaalla]

yea, i've seen websites say that the range for goldfish are pretty much the range of cold water to tropical fish warm water. goldfish are pretty but they just seem to create a lot of waste. it maybe they have more mass than tropical fish, but i think you would just need to do more water changes and keep an eye out for things that look out of the ordinary.

[Zodiac007]

here's a video of the 3 goldfish in the 10 gallon, I used a cell cam so it has bad quality

http://www.youtube.com/watch?v=NyTpGL0trEI

[Fishguy2727]

Yes, they are messy. No one is disagreeing with that. But that doesn't prove they are any worse than the same size cichlids at the same temperature, for example. I have had lots of goldfish and never seen anything that actually shows they are any messier.

Do you have any? How many?
Rather than regurgitating someone else's work, do you have anything to support this? The internet is not always reliable and you can find something on the internet to support any opinion you want.

Rather than fill this thread with overwhelming amounts of text, please go into my blog or the Goldfish section in the Coldwater section and read the article on 'Myths about Goldfish and their Care'. This one has actual references to support the information, not just someone's word and that's it.

They are messy, but per weight not any messier than any other fish.

Yes, they are from sub-tropical to tropical areas but have developed stable populations in the same waters as most of our tropical fish are from. So yes, there are literally goldfish in the Amazon swimming along side of tetras, plecos, discus, angels, etc.

All fish need more oxygen as the temp goes up. The same rules that show goldfish do apply to tropical fish as well, so I am not sure what that has to do with anything.

Stick a cichlid or pacu in the same conditions described in that link and you will get the same results, a dead fish.

[MCHRKiller]

I have a feeder gold in my 55G planted, it was left over from the days of keeping piranha...it survived with them for many months until I gave the remainder of my shoal to a friend. I tossed the feeder into my then 40G planted...its since been upgraded to a 55G and hes an impressive algae eater....one of the best ever. And before anyone jumps on you for your feeders lack of growth...Ive had this feeder for over a year and its grown like an inch...and the smallest tank it has ever been in is a 40G. Feeders are genetically screwed up IMO, theyve been so over bred and fed growth hormones that sometimes youll get one thats growth rate is extremely slow. I also agree that per weight they arnt any worse than a big cichlid or catfish, even then with good filtration and a good diet it isnt bad at all. People are usually shocked at how little waste comes out of my 150G tanks gravel. My parents garden pond isnt any worse and it only gets cleaned in the spring.

[MrJim]

here's a video of the 3 goldfish in the 10 gallon, I used a cell cam so it has bad quality

http://www.youtube.com/watch?v=NyTpGL0trEI

Nice looking tankthumbs2:

[labnjab]

I have 4 fancies in a 75 gallon (upgraded from a 55) ranging from 3 inches to just over 6 inches and they are less messy then my 55 gallon community tank. When they were in my 55 I never had to vac the sand (I tried, but never got anything) and nitrates never got over 10, while my community tank I have to vac every 2 weeks. My angel fish of similar size (but less weight) produces more waste and is a bigger pig then they are

[Eddie]

Goldfish are a cold water species and will grow far too big for their current tank, they also put out too high a bioload for what you currently have set up.

[tanks4thememories]

Yes, they are messy. No one is disagreeing with that. But that doesn't prove they are any worse than the same size cichlids at the same temperature, for example. I have had lots of goldfish and never seen anything that actually shows they are any messier.

Do you have any? How many?
Rather than regurgitating someone else's work, do you have anything to support this? The internet is not always reliable and you can find something on the internet to support any opinion you want.

Rather than fill this thread with overwhelming amounts of text, please go into my blog or the Goldfish section in the Coldwater section and read the article on 'Myths about Goldfish and their Care'. This one has actual references to support the information, not just someone's word and that's it.

They are messy, but per weight not any messier than any other fish.

Yes, they are from sub-tropical to tropical areas but have developed stable populations in the same waters as most of our tropical fish are from. So yes, there are literally goldfish in the Amazon swimming along side of tetras, plecos, discus, angels, etc.

All fish need more oxygen as the temp goes up. The same rules that show goldfish do apply to tropical fish as well, so I am not sure what that has to do with anything.

Stick a cichlid or pacu in the same conditions described in that link and you will get the same results, a dead fish.

Oooook I see you where you are taking this. It wasn't my intention go take this tone but ok you wish to have it so you got it.

1) Please provide links to blind statements you spew forth as if you are "The authority " on a given subject. As in I had to look for and read your reference to http://www.aquaticcommunity.com/aquariumforum/showthread.php?t=32662&highlight=myth since you compiled it, it would have been nice if you also linked it for those who actually read with an open mind not just to further their point. In your own article you go on to state and I quote:
"“Goldfish are coldwater”
This isn’t completely a myth, goldfish are definitely well adapted to cold water. They can live in water down to the freezing point, as long as it stays liquid. The myth part of this is that they can only be in cold water."

If you read the articles I actually took the time to link oh im sorry to use your lingo "Regurgitated" (By the way an essay is when you research and recompile information on a given subject. however in a simple answer to someones question on a thread one typically "Regurgitates" in order to save time and energy. A responsible person chooses what they "regurgitate" based on previously accumulated facts and knowledge. Not just willy nilly choosing anything they already believe just to make a point.). Anyway if you read your own work you will see that you are saying the very same thing the articles I cited are saying. And much of the same things I am saying with one major deviation You choose the word "Thrive" in tropical temperature environment and I use the word "survive". You are so quick to prove your point and shoot down any possible validity in what im saying and I quote "Do you have any? How many? Rather than regurgitating someone else's work, do you have anything to support this? " That was uncalled for and sets the tone I now use in my response. Please explain how your article is anything more than you reading and possibly experiencing SOMEONE ELSE'S WORK and regurgitating it in a new package? Where are YOUR clinical trials on the subject matter posted? Where is your white paper on this subject posted in "Scientific American"? So please lets be real here and stick to the facts as we see them, can cite them in OTHER PEOPLES WORK, and let readers and intellect decide.

2) In my 20 Plus years of actual experience with aquatic life: I have been professionally responsible for and maintained multiple species of animals (for a friends reputable "High end" family owned pet store, not just some chain that doesn't care) my specialty was fresh water fish (including a large selection of Gold Fish), Several tanks and ponds on the premises were dedicated to Display only and it was at my discretion as to their content and display. At least one of the display only tanks was dedicated to Cold water fish including Gold Fish, I was also responsible for pond maint. of vip customers with KOI, I also gained a lot of experience in rescue techniques of many fish including Gold fish because the owner had a thing where he would never refuse any fish a home, This was all as lead FW specialist on a part time basis because it is not my field I only took job to help him out and support my fish habit. I have personally kept gold fish as pets for my toddler children in both tanks and bowls, I have also personally maintained feeder tanks with both gold fish, and minnows. It was my goal in my feeder tanks to keep them in the best possible environment to maintain their health. From time to time I had become "rusty" on certain topics but with a little help from a lot of people here and the several other forums I am a publishing member of I usually get refreshed. I hope this fits your qualifications for me to speak and "regurgitate" in a forum but I think my highest qualifications are an open mind and my knowledge that im not an expert authority by any means.

So back to the subject at hand

3) I personally believe that as one of the first aquatic creatures to be "domesticated"(if you can use that word for a fish...lol) Gold Fish are highly adaptive but that is different from "thriving." I also believe that there is a difference between a fish that was born into an environment and through generations of survival in that environment have grown tolerance for its extremes beyond their normal "Preferred" conditions, and what is available to the common hobbyist. The fish purchased by the average fish enthusiast are farm raised in cold water conditions and has been raised as such for generations. This also contributes to their general disposition towards that particular environment.

4) Your argument on fish waste: You say -
"They are messy, but per weight not any messier than any other fish."

It is a fact that Gold fish eat constantly and combined with the fact that Goldfish produce more ammonia than other fish per unit of mass because they are relatively inefficient eaters (they have to eat constantly because they don't do a good job of extracting nutrients from their food thus their stool contains higher quantities of partially or even un digested food - Stronger Ammonia content). There may be other fish that have the same issue but it is a commonly known FACT that gold fish do. I am sorry that as you say YOU have not noticed this, but your lack of attention to a specific detail or the fact that by some freak of science or maybe even what you feed yours, or your great filtration system, it is unobserved or non occurring in your tanks. That however does not make it untrue.

5) Cold Water : You say -
"All fish need more oxygen as the temp goes up. The same rules that show goldfish do apply to tropical fish as well, so I am not sure what that has to do with anything. "

Once again you may have read my "regurgitated" link but you missed the underlining content due to your prejudice of reading it just to prove your own point.
A fish that is accustomed to aspirating in cold water is accustomed to not working that hard for its oxygen, and requires a less efficient breathing system than one that is accustomed to such an environment. Because colder water holds more oxygen than warmer water. Yes it is likely that a gold fish can acclimate to non ideal conditions (conditions it was not bread for years to exist in), however it would require more vigorous breathing, more frequent trips to surface to breach than a tropical fish in the same water. I may also add that recent studies indicate that colder water requires less activity of the immune system of a fish because many pathogens are barely functional at lower temperatures. This has further possible ramifications in the realm of "adaptive defense" mechanisms in fish because a fish that has never been exposed to a particular pathogen is at a greater risk to deadly infection of said pathogen.

In closing Dude Ive read many of your posts and I like what you have to say in general and im sorry if disagreeing with you sparked you into some flame full retorts....lol And I am sorry for the tone of my reply but I did not like your whole "regurgitation holier than thou because I read stuff and rewrite it into a thread attitude...lol" You have valid points on the incredible adaptive abilities of goldfish and also on quotations with references. The pure science of the statements made on the links I provided stand on their own behalf and I leave it to the reader to find more information as I was only helping out with a nudge in the general direction on the topic. It is often in disagreeing that we strengthen our knowledge if met with an open mind.

[tanks4thememories]

Yes, they are messy. No one is disagreeing with that. But that doesn't prove they are any worse than the same size cichlids at the same temperature, for example. I have had lots of goldfish and never seen anything that actually shows they are any messier.

Do you have any? How many?
Rather than regurgitating someone else's work, do you have anything to support this? The internet is not always reliable and you can find something on the internet to support any opinion you want.

Rather than fill this thread with overwhelming amounts of text, please go into my blog or the Goldfish section in the Coldwater section and read the article on 'Myths about Goldfish and their Care'. This one has actual references to support the information, not just someone's word and that's it.

They are messy, but per weight not any messier than any other fish.

Yes, they are from sub-tropical to tropical areas but have developed stable populations in the same waters as most of our tropical fish are from. So yes, there are literally goldfish in the Amazon swimming along side of tetras, plecos, discus, angels, etc.

All fish need more oxygen as the temp goes up. The same rules that show goldfish do apply to tropical fish as well, so I am not sure what that has to do with anything.

Stick a cichlid or pacu in the same conditions described in that link and you will get the same results, a dead fish.

PS Im reading some of the links on your temperature position and I must say it is very compelling. In fact it has inspired me to do some further research on the info. I will keep ya posted on what I find. Im also thinking alot of the farms may have influence in the preferred temperature of goldfish that we buy in stores. What do you think?

[Fishguy2727]

Do you have anything that shows that they produce more ammonia per weight? Like a scientific article or anything?

As stated in my articles, their ability to properly digest food is not based on them, but the quality of their food. If you give them food with low quality ingredients that they can't digest then yes, it will come right out the other end.

How are you defining 'thrive' and differentiating it from 'surviving? If goldfish are growing well, have great colors, great health, and are reproducing how are they not thriving?

By regurgitating I meant simply copy and pasting things from other sites. I did actual research when I found different scientific articles, compiled them, analyzed them, and wrote my own article based on that analysis.

Most fish farms are in Florida or Southeast Asia, far from coldwater.

Goldfish are by definition eurythermal. They can live and thrive in a VERY wide temperature range, from almost freezing to above 100F. A true coldwater species would be stressed above a given temperature. True coldwater fish are things like trout and white cloud mountain minnows. They become stressed above certain temperatures and cannot thrive. This is not true of goldfish, who can not just survive in but truly thrive in the exact same temperatures that tropical aquarium fish are kept in.

It is not an inefficient digestive system that explains their constant eating. They are herbivorous omnivores. Like all herbivores and herbivorous omnivores they are constantly foraging on very small amounts of food at a time (algae, plants, small invertebrates, etc.). This doesn't mean they are inefficient. In fact most aquarium fish are the same way. Everything from mollies and platies to tetras and danios all naturally feed on many small meals per day. The fish that do not have this type of feeding style are the highly carnivorous fish, like the big fish-eating cichlids. These fish have very large stomachs capable of taking large meals very infrequently.

If a goldfish is having problems getting enough oxygen it is because there is not enough aeration. I have had them in tanks over 80F and they do not gasp, make extra trips to the surface, or have to work harder for oxygen unless there is inadequate aeration.

I think one thing being missed here is that the areas in which they are bred, Southeast Asia, Southern China, etc. are all tropical. In many cases freshly imported fish from these areas cannot simply be tossed in to room temp tanks. I have talked to numerous people who have imported directly from these areas and the fish must be kept in heated tanks for a few weeks and slowly cooled to room temp or else they become severely stressed, possibly ill, and can even die.

Where is the science in the links you reported? When I looked at them they were in popular article form and had absolutely no references. This means it was some person's ideas with no real factual support. The articles I have written are based on scientific journal studies that I personally looked up and analyzed. They are also based on my personal experience, the knowledge gained on forums (including goldfish only forums with very advanced and professional members), and based on what I learned getting my Biology degree.

Yes, where they are bred can have a big impact on their current ideal temp, but that doesn't mean that with the proper acclimation that they can't do just as well in other temps.

To anyone reading this:
PLEASE read through the articles I have written. I put a lot of time into them and have them on this forum for a reason. They are supported by actual facts, a lot of it is based directly on actual scientific articles, not just some experience with a fish tank. This doesn’t mean take them without question, but look at them and look at other sources. Decide for yourself what makes sense and seems more accurate and well-supported.

[Fishguy2727]

I forgot to post this earlier, it is also in the 'Myths...' article. The areas in blue are where goldfish are native. You can see that this includes areas that are definitely tropical. In addition, the areas in red are all countries where goldfish have now been introduced and have developed reproductive populations. As you can see there is no doubt that they can truly thrive in tropical water, no matter how you define tropical or thrive. Yes, this may not include fancy goldfish since they are not as hardy and will not thrive in as extreme conditions as long-bodied varieties.
http://i28.photobucket.com/albums/c207/reptileguy2727/Goldfish/mapwithcountries-1.gif

[Red]

Just a quick question for you and tank4memories, how close related is the common carp to a goldfish? Same family right?

[annageckos]

Besides being cold water fish and producing a lot of waste, I would think that the goldfish would eat at least some of your plants seeing how goldfish are very fond of plants. If not eaten they will most likely be uprooted.

Anna

[Fishguy2727]

They are in the Cyprinid family, same as danios, barbs, carp, minnows, etc.

As far as plants go in my experience it has more to do with the rest of their diet and not just that they are goldfish. Mine don't bother them at all VIDEO (http://www.youtube.com/watch?v=L62tOLUcg50). If the rest of the diet is truly complete and balanced they don't have a craving for anything in the plants. The same thing happens in humans. When you have a craving for a certain food it is because your body needs some nutrient that is found in it. So as long as the rest of the diet is good enough they shouldn't bother the plants. They have yet to uproot any of the plants in there.

[nyquil junkie]

I've had goldfish for years inside and out, they most certainly can be kept with tropical fish.
However you do have to consider a few things....
They get big. When they are big they get pushy and dig up your tank.
If your filter system can handle the bioload from big fish you are good.
Goldfish will adapt to freezing cold water or really warm water. In an outdoor pond they like to cruise around on the surface in the warm water, and then they go looking for shade or deep cool water.

They wont get sick from tropical temp water. They are very hardy and adaptable.

I've kept them in tropical tanks held at 80F and in unheated tanks that stayed around 60F. No problems.

BioLoad IS a problem, when they get bigger. A good bio filter will deal with it.

I like to put tiny goldfish in my tropical tank, and when they grow up I put them in a bigger unheated tank for a while then when they outgrow that, they get to go outside in the pond.

I don't think I've ever really lost a goldfish from the "stress", they are all very healthy piggys.

Trust me, if the water is good and the biofilter and plants can keep the ammonia/nitrite levels at near 0, goldfish are fine with tropicals.
If anything, the tropicals are the ones who wont fair well with the goldfish if you dont keep up good biofiltration.