Black cory’s cold water tank

[LCPete]

Unfortunately many fish are missold or have poor guidance by the stores that sell them, so you're not alone there by any means. This is why the photo of the fish was so essential since Cories are one fish that frequently get misidentified and that usually impacts the living conditions required for that fish.

It is very difficult sometimes not to get caught in the trap of misinformation where fishkeeping is concerned. I understand the dilemma of the heating costs but if you use a heater in the temperate aquarium, set at 20 or 21 degrees that will enable the Cories to thrive without costing the earth to run in electricity....lower temperature and a well insulated home will mean the heater needing to come on will be less but it will be there should the temperature drop for any reason, it would be a backstop rather than an essential for keeping things tropical enabling the fish to stay healthy and as reassurance for you that they are not getting too cold.

When I had temperate fish I always had a heater set at around the 20 degrees just incase of problems such as a cold snap...the heater was always there should it be needed

Thanks that’s an excellent idea a heater set at 20 just in case

 

[Deleted member 149562]

One thing you may discover with them at or close to their minimum ideal temperature, excessive egg production..

Cories are notorious for getting "excited" in cooler water, such as right after a water change or if the ambient temperature is on their physical minimum such as in a temperate aquarium setup.

Unless a population explosion is wanted, you might wish to scrape eggs off as soon as you see them, if their tankmates don't get to them first.

 

[DoubleDutch]

One thing you may discover with them at or close to their minimum ideal temperature, excessive egg production..

Cories are notorious for getting "excited" in cooler water, such as right after a water change or if the ambient temperature is on their physical minimum such as in a temperate aquarium setup.

Unless a population explosion is wanted, you might wish to scrape eggs off as soon as you see them, if their tankmates don't get to them first.

That isn't entirely correct. Their hormons / breedingbehaviour is triggered by weatherchanges, pressurechanges and cooler water after a warmer period (start of the rainy season).

Simply keeping them cooler all the time won't have a direct effect on that.

 

[Deleted member 149562]

That isn't entirely correct. Their hormons / breedingbehaviour is triggered by weatherchanges, pressurechanges and cooler water after a warmer period (start of the rainy season).

Simply keeping them cooler all the time won't have a direct effect on that.

I only mentioned it since my old temperate aquarium had two very juvenile Peppers due to overstock elsewhere (too young to actually sex) and when moving to a different aquarium the two juveniles had grown up and become 10 Peppers....which wasn't exactly planned. The other Peppers in normal temperature aquariums had not reproduced any offspring in the same timespan. So knowing that temperature changes can sometimes bring on the breeding instinct, I thought maybe the slightly lower temperature in the temperate aquarium had caused an increase of activity.

I guess I am incorrect on that, but it is an understandable assumption to make.

Thank you for correcting me.

 

[mbsqw1d]

What other fish will you be keeping with the corys? I went down this "temperate" road once and ended up struggling for options. Barbs and danios are good, happy down to 16c - but I ended up finding out that barbs and Cory's aren't a good mix..

 

[LCPete]

What other fish will you be keeping with the corys? I went down this "temperate" road once and ended up struggling for options. Barbs and danios are good, happy down to 16c - but I ended up finding out that barbs and Cory's aren't a good mix..

Am going with shrimps and Endlers guppy’s won’t be getting barbs as I’ve got barbs in my other tank and can’t mix barbs and shrimp
not sure what else to get maybe some White Cloud Mountain minnows am still thinking about what to get

 

[Byron]

@LCPete I've no idea as to your level of knowledge with fish, so forgive me if this is already understood, but in case it is not, it is very important in understanding the significance of temperature.

You are correct that the temperature range on reliable sites is based upon observation in the habitat of the species, and often over a year. The suggestion one frequently encounters that there is some considerable variation in temperature diurnally and seasonally is not truly accurate in the true tropical regions, such as the Amazon basin, as in most cases the temperature varies by no more than a few degrees if that. But variation is not the same thing as permanent.

Ranges for a species on reliable sites are intended to be read as the range within which the fish should manage, but not exclusively at the lower end or the higher, but more in the middle. In the example with the two cory species, the ranges of 21-27C and 20-26C respectively mean that the fish will tolerate (using Ian's words here) the extremes for short periods but should be maintained long-term at 24-25C.

One might wonder why this matters. Fish are ectotherms; they do not generate internal heat but depend upon the temperature of the water in which they live to provide the heat necessary to live. Temperature is a prime driving force in an animal's metabolism, and each species has evolved to function in a specific temperature. Some species have much greater variability than others. But their metabolic functions need "x" warmth to work, even though the fish may manage/tolerate temporary periods outside this preference.

 

[Fishfinder1973]

Corys won’t just keep breeding when kept at a constant cool temp.Like DoubleDutch says,it’s to do with the rainy season,so if your tank water is kept at a constant 25 and you do a water change and refill with cooler water,say 22,then there’s a very good chance of eggs within a day or two.
I keep my tank at 22 and during a water change I will refill with water at 22.I rarely see Cory eggs now.
Wether or not they will be ok in water at 18 I don’t know,but I’m sure that even in their natural habitat the temp will go lower on occasion,but long term I’m not sure.

 

[LCPete]

@LCPete I've no idea as to your level of knowledge with fish, so forgive me if this is already understood, but in case it is not, it is very important in understanding the significance of temperature.

You are correct that the temperature range on reliable sites is based upon observation in the habitat of the species, and often over a year. The suggestion one frequently encounters that there is some considerable variation in temperature diurnally and seasonally is not truly accurate in the true tropical regions, such as the Amazon basin, as in most cases the temperature varies by no more than a few degrees if that. But variation is not the same thing as permanent.

Ranges for a species on reliable sites are intended to be read as the range within which the fish should manage, but not exclusively at the lower end or the higher, but more in the middle. In the example with the two cory species, the ranges of 21-27C and 20-26C respectively mean that the fish will tolerate (using Ian's words here) the extremes for short periods but should be maintained long-term at 24-25C.

One might wonder why this matters. Fish are ectotherms; they do not generate internal heat but depend upon the temperature of the water in which they live to provide the heat necessary to live. Temperature is a prime driving force in an animal's metabolism, and each species has evolved to function in a specific temperature. Some species have much greater variability than others. But their metabolic functions need "x" warmth to work, even though the fish may manage/tolerate temporary periods outside this preference.

Thanks Byron for the detailed informative reply appreciate it
I do see what you mean that how the fish functions is governed by temperature and although a Cory may survive outside it’s normal range it won’t thrive and do well
I won’t now be getting of the Corydoras panda that I was thinking of
Thanks again everyone for the help and advice very glad I joined this forum