Why can't I keep goldfish with tropical fish?
- Thread starter Kevin007
- Start date
You can't trust every website on the internet. Goldfish are coldwater fish, meaning about the highest temps. they can handle are in the high 60's F and lowest they can stand (from what I've heard) are in the low 30's F. They do not do well at all in tropical temp. setups. It causes their immune system to weaken, among other things. Tropical fish can handle temps into the mid 80's F and down to the low 70's F. Really, anyone can create a website and put just about whatever info they want to put on it. Fishbase.org, fishgeeks.com, and this website are reliable sites to get info from. The first 2 sites I listed have indexes of fish profiles, so you can read up on goldfish that way.
I don't know where you live...but tell her we humans can survive in Death Valley or Antarctica (whichever is more appropriate)...doesn't mean we should try...
1) putting goldfish and tropicals in a tank that has a low temp for the tropicals and a high temp for the goldfish will make them all uncomforable, stressed and weaken their immunity to all possible health problems
2)tropical fish like very clean water and goldfish are probably the dirtiest thing you could put in there with them. they pollute a lot and cause massive amounts of ammonia
3) goldfish grow fast and get real big if they are cared for properly. it is possible that they might eat smaller tropical fish when they become large enough to, and that won't take long if you aren't stunting them.
2)tropical fish like very clean water and goldfish are probably the dirtiest thing you could put in there with them. they pollute a lot and cause massive amounts of ammonia
3) goldfish grow fast and get real big if they are cared for properly. it is possible that they might eat smaller tropical fish when they become large enough to, and that won't take long if you aren't stunting them.
Dangerdoll
Global Moderator
ok in addition to those...
they also have different food requirements.
The reason goldfish like cooler water is for the oxygen content. If the tank is cooler, the oxygen content is higher.
When the goldfish continue to grow and the guppies remain at their small size, the goldfish tend to like more than just looking at them.... the aquire a taste for them.
they also have different food requirements.
The reason goldfish like cooler water is for the oxygen content. If the tank is cooler, the oxygen content is higher.
When the goldfish continue to grow and the guppies remain at their small size, the goldfish tend to like more than just looking at them.... the aquire a taste for them.
Fish can only produce as much ammonia as the protein in their food allows; they cannot manufacture nitrogen atoms out of thin air. If goldfish produce more ammonia than other fish it's simply that they eat more so you put more food in. This should always be borne in mind when a given fish is called a "big waste producer". The only real waste producer is fishfood.
Given the temperature garden ponds even in the UK reach in the summer, and the rather large and healthy goldfish I've seen in ponds in Kew Gardens in the tropical houses, I doubt if temperature is really an issue with goldfish. The reasons I would give are:
1) Size. Goldfish will quickly reach a size where they will predate many tropical species - guppies included. But you could say that about a lot of tropicals as well.
2) Food. Goldfish are largely vegetarian. But so are silver dollars, mollies, you name it...
3) It just looks wrong. Subjective, but significant when an aquarium is an aesthetic object. But I'd say the same about sunken galleons, Greek columns, corals and God knows what some people put in their tropical freshwater tanks.
4) Size. Common goldfish are too large for most tanks. Also true, however, of many tropicals.
5) Finnage. The fancy varieties are going to get minced by many popular fish. But this is, again, true of many tropical species as well.
Darnit. Can't actually think of a good reason which isn't also true of some tropical species. I wouldn't do it myself because (a) I like to keep wild type specimens of fish rather than domesticated forms (I don't mean actual wild fish, I mean, for example, angelfish with vertical stripes rather than black, koi, or any other variety) which goldfish aren't, and (b) they'd eat my plants.
Given the temperature garden ponds even in the UK reach in the summer, and the rather large and healthy goldfish I've seen in ponds in Kew Gardens in the tropical houses, I doubt if temperature is really an issue with goldfish. The reasons I would give are:
1) Size. Goldfish will quickly reach a size where they will predate many tropical species - guppies included. But you could say that about a lot of tropicals as well.
2) Food. Goldfish are largely vegetarian. But so are silver dollars, mollies, you name it...
3) It just looks wrong. Subjective, but significant when an aquarium is an aesthetic object. But I'd say the same about sunken galleons, Greek columns, corals and God knows what some people put in their tropical freshwater tanks.
4) Size. Common goldfish are too large for most tanks. Also true, however, of many tropicals.
5) Finnage. The fancy varieties are going to get minced by many popular fish. But this is, again, true of many tropical species as well.
Darnit. Can't actually think of a good reason which isn't also true of some tropical species. I wouldn't do it myself because (a) I like to keep wild type specimens of fish rather than domesticated forms (I don't mean actual wild fish, I mean, for example, angelfish with vertical stripes rather than black, koi, or any other variety) which goldfish aren't, and (b) they'd eat my plants.
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when kept in tanks, diet and temp are the biggest differences. goldfish would not last long in the upper 70's or lower 80's.
although some tropical fish may be herbovorious, they also appreciate some protien in their diet. tropical flakes usually provide a good mix of protien and carbs for the vegetarian fish. on the other hand, goldfish should not have very much protien in their diets at all.
although some tropical fish may be herbovorious, they also appreciate some protien in their diet. tropical flakes usually provide a good mix of protien and carbs for the vegetarian fish. on the other hand, goldfish should not have very much protien in their diets at all.
I think the point is that if you keep a goldfish in a tropical tank, its going to eat way more protein than it should because...well...goldfish are dumb and will eat anything that will fit in their mouths and that includes tropical fish food (which usually has some form of protein) and possibly tropical fish (which are definitely protein). Thus we have a goldfish pooping a lot of ammonia rich poop due to its high, albeit delicious, protein diet.
This is all very good information,however it has been my experience that most fish species can adapt very well.This is also true for gold fish.I have kept gold fish in tropical tank's with several different fish species including angel's,tetras,guppies.Do they produce more amonia(yes,according to the above post's)but it's nothing weekly water changes can't handle.Can they handle higher temp's(no,according to the above post's)but mine have been doing fine for years,even thriving.I'm not knocking the above post's ,but imo and has been my experience that gold fish aswell as many other species can survive and thrive in conditions that are not optimal......
Only if you stuff the food in; that was my point. The way some people talk you'd imagine that goldfish/oscars/pacu (you name it) could create ammonia out of thin air.
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