Winter heat

[Guyb93]

I’m fighting my own brain again , this time of year the only thing I really monitor on my tabk is temp, battling the elements to keep that green zone of 76-80f yet my logic is saying to me there is no possible way that the South American river system in winter months is at this temperature, I’m guessing it could drop as low as 60f , so my question why do we battle to keep a constant temperature when it’s not natural , is keeping your fish in a constant summer healthy ?

 

[kwi]

I recently read an article on temperature stability in tanks and how we strive too hard to maintain it, the gist was that if the changes weren't too abrupt and stayed in range we shouldn't sweat it.
The only good reason to maintain a tightly controlled temperature was to prevent spawning.

 

[Guyb93]

I recently read an article on temperature stability in tanks and how we strive too hard to maintain it, the gist was that if the changes weren't too abrupt and stayed in range we shouldn't sweat it.
The only good reason to maintain a tightly controlled temperature was to prevent spawning.

Yeah I know a fast increase or decrease in temperature is bad but my tank has been slowly dropping the last month or so I usually keep 28c and now it’s around 26 and having to keep a second heater on constant to maintain tht if I just use the one it will drop for example I woke up in morning to 26.2 fine Il turn the second heater off by the time I get back from work it will be around 25.8 still fine but off that drop I’m looking at room temp of about 20c after 48 hours of only using 1 heater and a single heater will maintain that temp I just think it feels cold in there and start to worry , I’m just confusing my self from research the Amazon river system doesn’t really hve a winter being around the equator so does this mean tht they are more susceptible to temperature changes rather than say Asian or Central American fish who have a more defined season pattern or being tank bred is temp not so much if there dna requirements any more

 

[kwi]

Actually studies show cold water fish are more sensitive to water temperature changes.

 

[Guyb93]

Actually studies show cold water fish are more sensitive to water temperature changes.

So in theory It would be worse keeping a goldfish at 80f than a pleco at 70f , I’m just looking for any excuse to not deal with low temp or I’m going to end up with 5 heaters never had this problem with my 250l but my 500l temperature drops a lot easier

 

[kwi]

If I recall correctly this was proper cold water fish, sort of 4c and deep enough to not get any influence from the surface

 

[Wills]

Some people do do winter mode on their tanks there are some fish that need this called Gymnogeophagus if they are kept at the same temperature for too long they die very young.

 

[The Lumpfish Guy]

If I recall correctly this was proper cold water fish, sort of 4c and deep enough to not get any influence from the surface

Yeah so what you are talking about there is species which have adapted to very cold very stable environments. But most fish which dwell near the surface (using >500m as "surface") can tolerate some form of temperature shift. Several Antarctic species temperature ranges can cover 4 degrees (-2 to +2). This is why you always see temperature ranges for fish quoted.

It really comes down to a species specific level the extent of the temperature swing but It is not unrealistic to expect lower temperatures in winter. I also think we discussed on a different thread a while ago about potential diurnal temperature fluctuations, but don't remember how that went.

As I am sure you are aware fish's temperature is wholly dependant on the water they are in ( baring a few exceptions) so lowering temperature generally reduces metabolism and thus food intake required will be less, while increasing temperature will increase this. I personally use this if I have to go away from the tanks for a longer time than say just a weekend, just reducing by 1-2 degrees over a short period before leaving can help slow the metabolism (thus need for food) and also waste production.

Now if you have juveniles or larvae they are usually more sensitive to temperature fluctuations. But if you just have adult fish you can get away with reasonable temperature fluctuations within the species "range".

Also If you are wanting to breed fish, temperature has a huge role in egg quality in most species, and finding this "optimal" temperature for the female (and to lesser extent male) will improve egg number, fertilisation and hatching percentages, and reduce deformities.

 

[mcordelia]

What a timely question! I've been thinking about this myself lately, since we keep our house at 65f (18c) during the winter and 72-75f (22+c) during the summer. The way I am planning on addressing it is to buy big enough heaters (probably trying for 2 watts per gallon or a little over) to keep the tank around 75f during the winter, and if it then naturally stays warmer in the summer so be it. In my case, to avoid hot spots in the tank, I would go for multiple smaller heaters than one big one (also creates a buffer in case one breaks), and place them into water flow so that the coldest incoming water (from the filter) gets warmed up first and circulates into the tank, with fewer dead zones.

 

[Colin_T]

I used to run my tanks at 18C. That is how cold they got in winter but in summer they went up to 30C+ due to the hot summers. I also had fish outside in ponds and the temperature dropped to 5C in winter and over 40C in summer. The temperatures go up and down slowly over months and the fish were fine.

I used to check water temperatures when collecting fish. I was in the south-west of Western Australia and found Lepidogalaxias salamandroides in a pond that was about 6 feet deep at the deepest part. The temperature at the bottom of the pond was 10C and the temperature at the surface around the edges was 30C. There were juvenile salamanderfish around the edges in the warm water and their parents were at the bottom where it was cold.

I have checked temperatures on other ponds and waterways in the south-west and found similar variations with different species of fish found at all levels.

Fishes found in the Amazon and around equatorial regions don't have the same extreme variations in temperature as we have in Australia, but there is still some variation and they can tolerate it fine as long as the temperature changes slowly over time (weeks or months).

 

[AbbeysDad]

Quite some time ago I made a fascinating discovery... Among other tanks in my unheated basement (55°F in winter), I have a 5 foot kiddie pool as a pond. I scoop duckweed from the 110g stock tank and dump into the pond as it's supplemental food for the turtles. Unintentionally some swordtail fry made the trip with the duckweed. They grew out and are living large. Even in summer, I do partial water changes here with cold well water. They seem unaffected. I imagine there could be shock at to rapid a temperature change, and there may be species much more sensitive to temperature ranges. But some can tolerate temperatures all tropical fishkeepers have been programmed to fear. Now most of my tanks (with heaters) are at about 75°F. The room temperature in my living room is typically around 70°F. One could argue that the fish would be okay at "room temperature". But might they be happier, healthier, and breeding better at stable temperatures of 75°F - 78°F ? ... and then there's discus, that do best at even higher temperatures.
So maybe you don't 'need' a heater...but maybe you do.