Tropical Fish Kept In Cold Water ! ?

[Zincubus]

Just wondered if anyone else has had similar experiences ?

A few years ago we were left without electricity for about 15 hours so I expected the worst .

Anyway the next day there were no problems in fact they seemed contented if slighlty slower and less hungry.

I have kept quite a few different TROPICAL fish in a small ( 12x7x6 ) unheated tank .
All have thrived - I used it once as a place for my ODDS and SODS .
List of fish - Golden schubert barbs , checkerboard barbs , mollies , neons , glowlights , guppies, flying fox, plecs, glass catfish,.... plus others ...and one 5 " Blue Eyed Cichlid !!

 

[fishyfeet]

Fish not kept at the correct temperatures will cause them stress and therefore likely to suffer from related diseases, although they may survive, in time they will live shorter and less full lives. I bet they arent as active either. di

 

[Colin_T]

I allow my tanks to cool over winter. They normally sit around 26C in summer but I have the heaters set for 18C. In the cooler months the water temperature gradually drops to 18C where it stays until the weather warms up.
The cooler water slows their metabolism and they eat less and aren't as active. But I don't have to do as many water changes because of this and as soon as the water warms back up they all start dsiplaying and breeding.

NB, my tank temperatures drop slowly over a course of months and is slightly different to having a power failure or heater fail and the temp drop overnight.

I have had heaters fail and the tanks have been cold in the morning. Some fish die but others are fine.

 

[Eclecticoldsod]

100% behind Colin on this. A constant all-year-round temperature has to be unnatural for all but the most 'tropical' of fish – and even they must experience a drop in temperature during the 'rainy season' – along with everything else that must involve.
I (in Britain) keep my heaters set to a low minimum, and allow temperatures to fluctuate day/night – summer/winter. I have never researched the subject properly, but reckon my lights increase the temperatures by a few degrees during the day, and the pump on the internal filter adds a degree or two at all times. The little light on the heater only comes on during cold nights in the winter (rarely in our 'so-called' summers – most years, anyway..!)
I would dearly love to know if anyone has ever done any real research on this subject...

 

[Zincubus]

Well I can only say that my experience has been positive ... the fish seem healthy and long lived and just slightly less active.
It is one of my spare tanks.