Tropical Fish In Cold Water

[bleepy]

I recently visited my LFS, and asked about what fish I could have in my coldwater tank that are a bit special, and not the general run-of-the-mill goldfish. I was told that I could purchase nearly 70% of the 'tropical' range, as they are not really that fussy. I purchased a large selection of these 'tropical' fish, and contrary to my original belief, they are doing very well, growing, and one of my Swordtail's is pregnant, along with a Paradise fish pair.


I have a range of other tropical fish, including Betta and loaches. How come these fish do not die, and can mannage to breed in water that is around 3 degrees cooler than they are supposed to be kept at?

Are tropical fish climatising or something, and just getting used to the cooler temperatures overall in England during their isolation periods? Kind of like a "passing-the-gene" type thing..?

If so, will there ever be tropical fish, or will goldfish and tropical fish just be "fish".. ex-tropical or not?

Any opinions or views would be appreciative on this matter.

Craig.

 

[Miss Wiggle]

hardy tropicals can 'survive' in a much broader range of conditions than we usually provide for them. common livebearers like guppies, platys and swordies will breed in just about anything.

what it is recommended to provide for them is ideal conditoons in which they will thrive.

by keeping them in conditions which are not optimum you arereducing their immune systems ability to fight disease and reducing their expected life span. While things may be fine for some considerable time you'll find that if you are hit by a disease it will be significantly more difficult to cure it as part of the treatment of any disease is to ensure optimum conditions (clean water, best possible diet etc)

 

[Robotochan]

The thing is, Coldwater is usually around 17C (at least it is in my house) so it's on the lower part of a lot of Tropical Fishes temperature limit. Wouldn't put a Betta in 17C water though, my one hates me when I do a water change with cold water and it only falls to 22C

 

[Colin_T]

Quite a lot of "tropical" fishes do get exposed to cool water during winter in their natural habitats. Neons for example have to tolerate 16degree C water in the amazon. A lot of rainbowfish from the northwest of Western Australia occur in water that fluctuates between 10 & 35C, depending on time of year. Livebearers that are in shallow pools have to tolerate sudden temperature drops during the cooler nights. In general most tropical fish can tolerate temperatures between 16 and 32C. However these tend to be the limits of the fish and they are stressed to some degree at these ranges.
If the fish are in the water while it cools down they will often tolerate it quite well. Problems occur when a fish is taken form warm water and placed in cold water.

A couple of years ago I was working on breeding some rainbowfish that could live outdoors all year round. I had Goyder river trifasciatas living in water that got down to a couple of degrees in winter and in summer went up to 35+.
I started with Melanotaenia praecox rainbowfish and after a couple of generations had them surviving at temperatures down to 8 degrees and up to 35 without any losses.

Most houses don't drop much below 18 degrees in winter and that is fine for the majority of tropicals. Discus and angels and labyrinths get miffed at these temps but barbs, tetras, catfish etc are normally ok. One of the advantages of keeping the fish in cooler water over winter is that they start to display and show off a lot sooner when compared to fish kept in warm water all year round.

 

[SJ2K]

Why dont you just by a heater for £12 and there you go, happy fish.

 

[Colin_T]

there's no fun in keeping fish in normal conditions Experiment on the little critters. Bwah ha haaaa.

 

[bleepy]

Thanks for the replies.. however, I forgot to state that the cold water tank I'm referring to actually sits at around 23c.. but I do have a few normal goldfish which seem to be happy. However, would standard goldfish, golden orfes and blackmoore's survive if I did install a heater (further to the previous comment)..? Obviously, with a heater I could increase my fish keeping horizons a lot further.. but would it affect them?

 

[Miss Wiggle]

same applies with golies in water that's too hot for them, it'd damage them, probably not short term but long term it'd cause problems.

this is why you shouldn't really keep golides and trops together, there is no optimum temperature to suit both, so you end up harming either group or both of them.

 

[Colin_T]

Goldfish and moors are fine at 23C. The orfes will be short term but they are a true coldwater fish. In fact the more fancy goldfish actually do better in warm water. As for warm water affecting goldies, the majority of them come from tropical asia where they are bred in huge numbers and live for many years.
If your tank sits on 23C then you can keep goldies and tropicals together as long as the tropicals like a slightly alkaline PH and don't pick on the goldies. Livebearers & catfish do well with them.
If you consider 23 coldwater, what do you consider tropical? Apistogrammas, discus & angels live comfortably at 28C but most other tropicals should be kept above 22 and below 28.

 

[rossyboy]

Just buy a heater, gradually increase the temp to optimum over a week or so.

 

[bleepy]

Well, to be honest I knew 23C was around tropical temperature, but given that my tank has no heating equipment.. I've always referred to it as a "cold water" tank.. seeing as it's not heated in any way apart from the central heating in the house.

 

[rossyboy]

yer, but the temperature is going to fluctuate without a heater. I'm no expert but i don't think it's good for the fish! A constant temp is preferred.

 

[bleepy]

The temperature of the tank only varies by 0.5 degrees at the most, as the central heating in my house is on constantly and maintains a constant temperature. I have a digital thermometer with an alarm just incase, though. The fish have been living qutie happily for several months now, and are growing, and as my first post stated, breeding! So they must be happy..

 

[rossyboy]

Yer i see your point.

But what ppl are trying to say is that although to you the fish might seem 'happy' they certainly wont thrive.

Also, livebearers would breed in a pool of filth lol (not literally)

 

[bleepy]

I completely understand what everyone is saying about the water temperature and the mixing of fish, etc. However, they're all getting along fine, and disease is rarely seen, anyway. None of my tanks have had a serious disease for around 6 years, now. Minor problems occur, like anyone's would every now and then, but I'm yet to have a fish that has suffered as a result of the problem.

And for the record, my tank is crystal clear and highly filtered (bar a bit of algae here and there for the bottom feeders and suckers etc).