Goldfish In With Tropical Fish

[raptorrex]

The article by Nathan Hill even states that there are no scientific reasons as to why they can't be kept together, I wonder where Raptorex has gone, I was anticipating his response.

lol, still here. just aint been able to visit the reference library. to get chapter and verse.

please dont get too hung up on the WASTING AWAY, part of my post. its the diminishing returns that were my main point. and most relevant to keepers here.

however. as we are asking for evidence.
how about some to prove Goldies are not temperate fish. its, and has been, the prevailing view they are.
even your linked article , noted the increase, in the already high, waste at higher temps.( it also made the statement that tropical fish are known as such for, geographical reasons. not because of the temperature fish live at.)
so evidence to backup the NO MORE WASTE than A Tropical fish, would help too. as, again, that is the prevailing view.

also as far a Laos being the "origin" of goldies. as China is the stated place of origine, as far as i can find.

you will have to forgive the delay. time needed for research is limited, for me.

 

[fishguy2727]

They produce more waster in a higher temp than at a lower temp, just like a 'more' tropical fish would also produce more waste at an even higher temp. However, IME that waste production is not higher than the same bioload of tropical fish at the same temp. As in, if I have two tanks, both at 80F and one has a certain mass of cichlids fed a certain amount of food and the other has the same mass of goldfish fed the same mass of food the waste production in each tank would be effectively the same. I can't really prove this with exact ammonia concentrations produced by each tank in an uncycled setup, but out of the tanks I have maintained they run the same. Waste production is based on a few factors: temp, mass, food input, etc. There is nothing magical about goldfish that makes them produce more waste than these factors will dictate.

The map I posted explains it quite well but I guess words are helpful too. Just because hobbyist sites cite China as the origin of goldfish, you need to understand what they mean. When they state they are from China they are probably referring to them in captivity. Yes, they are naturally from China, but they were domesticated there too, so that is where most breeds are from (like a Labrador Retriever being from Canada). However, their natural range is more than just China. Here: http/fishbase.org/Country/CountryList.php?ID=271&GenusName=Carassius&SpeciesName=auratus+auratus you can see a list of all the countries goldfish live in the wild and whether they are native or introduced in that country. This is not a hobbyist site. The information is maintained by scientists and used by scientists, so it is more accurate than hobbyist sites. It specifies that their natural range includes China, Hong Kong, Japan, Laos, Macau, and Myanmar.

The 'diminishing returns' means the same thing. However, IME they grow best in warmer temps. Of course there is an upper limit where it will become a problem, but it is not in the temp range hobbyists keep tropical fish in.

 

[mark4785]

I think it is a much wiser choice to keep Goldfish in pond conditions or a cold water aquarium. I believe this because there are some people that experience issues looking after the welfare of tropical fish in heated aquariums during the occasional heatwave that we may experience in the UK so it would be cruel to think that a goldfish would survive such water temperature rises.

In addition, seeing as the majority of people associate goldfish with cold water and thus keep them in such a water temperature, introducing them to a tropical aquarium would not be practical due to the vast difference in temperature.

I do agree that goldfish can be kept in warmer water as I've experienced my pond water temperature rise ot 24-25 degrees C without hindering the goldfish but I think to prolong these conditions has virtually no purpose since they will age quicker, produce waster quicker and there is an increased risk of fungal, parasitic and bacterial problems flourishing. In addition, there is evidence that I've come across that suggests that a constant high temperature can decrease the likelihood of the goldfish wanting to breed since seasonal variations in temperature (light levels also play a role in this) act to induce breeding behaviour.

By all means, mix your goldfish with tropical fish, but doing so will just create problems on a practical and welfare level in my honest opinion.