2-degree Temperature Swing Each Night

[Evad]

Need your opinion on whether a 2-degree temp drop over 12 hours is OK for a community aquarium. The temperature drop happens at night over about a 12-hour period. The temp starts at 80 degrees and drops to 78 degrees by morning. Sometimes the drop is smaller but I have not seen it bigger.

This is a 180gal tank so for the most part the conditions of the tank are very stable. However it is kept in a cold basement and thus the temp swing. I could add another heater I suppose but would need to swtich it on/off to work only after my 640 watts of lighting turn off otherwise I will trip a fuse. That is a hassle I would like to avoid if you think angelfish, cories, glass cats, farowella, and a few other fish can handle the change.

Thanks in advance for your advice!

 

[Tolak]

I have a 150 gallon tub outdoors, 1,000w heater on a programmable heat controller. It is set for a 2F variance, turns on at 76F, off at 78F. A couple degrees variance will not hurt any fish I can think of, the tub has platys, corys, & bristlenose. Good luck counting the platy fry.

 

[Evad]

You must be a mind reader because I do have platies but I did not mention them!

However, I only have male platies in my tank so no fry.

 

[Biulu]

My temperature also drops between 1 and 2 degrees every night. I have not had a problem with it so far.

 

[Bignose]

Bodies of water in the wild change by a lot more than 2 degrees in a day on typical days and yet the fish seem to survive just fine.

Once people start reading about all these fish disease and thermal and pH shock, usually people start underestimating just how hardy fish are. Give your fish your fish good water, do the water changes every week, feed them a variety of foods, and they can live very long and happy lives. If ever in doubt, just look at Nature. Fish have survived a long, long time (evolutionarily speaking) and they can take a lot of what nature throws at them. Monsoons, floods, droughts, etc. It is not uncommon for bodies of water (like ponds, lakes, rivers) to have swings of 10 degrees F or more during the day as the sun comes out and then sets. 2 degrees a night is comparatively nothing.

 

[afireinside]

Yes, like Bignose said, naturally in the wild, there would be a lot more than 2 degree temperatures in the water. Your fish will be fine.

 

[Evad]

Thanks all! Is 80-78 and ok temperature to keep a community tank at? Or should I come down a degree or two?

 

[shelaghfishface]

i had mine up to 80 and was advised for the fishes and plants beneifit to turn it down to 75, but you could afford a little higher if your tank is fluctuating, say 77/78..great idea by the way!
shelagh xxx

 

[ALEXF]

i think the shock comes in to play when it just BOOM drops 2 degrees. Even in the wild it gradually gets cooler and then gradually gets warmer. now if you chucked some ice cubes in there you might have a problem i would think but the 2 degrees isnt a big deal because it is gradual as the house cools off.

 

[Tolak]

I'll drop the tank temp 2-4F in a couple of minutes doing large water changes. This is a common way to induce spawning in many species.

I set that tub up a couple weeks earlier than I had planned, a buddy happened across about 40 African cichlids, with no spare tank space for those fish. My tanks were packed as well. I had everything but the controller, which meant plugging & unplugging the heater. That tub swung between 76F-90F daily for a few days, no losses.

 

[ALEXF]

so basically when introducing new fish its not the shock of the temp that kills them its the shock of different water quality?

 

[Tolak]

Usually hardness more than pH or temperature. I breed corys just to keep angel tanks clean, I'll take a net full of corys from a tank that is 75F, walk across to an angel tank that is 85F, and put them in, with rarely a loss. I do the same with angels, 2-3F difference. Hardness & pH is the same in all tanks.

What will often kill new fish is being exposed to bacteria & such that your current stock is living just fine with. New fish, being shipped to a shop, bagged withing days, then brought to your house, have been stressed. Stress lowers immune response, making them more susceptible to an opportunistic infection. This is one reason why a quar tank is a good idea for new purchases.

 

[Evad]

I guess if you think about it, introducing new fish is a lot like visiting another country - you might catch something because your body is running into germs that it normally never encounters.

 

[Tolak]

Take that, and add in skimping on sleep for a few days before, and perhaps doing some heavy drinking a couple nights before to lower your immune response. Get exposed to some new pathogens with a lowered immune system, and you are almost sure to get a little bug of some sort.

 

[MarkByrom]

It's when you turn your tank lights off. Get a better heater, or two small heaters at each end of the tank, this should stamp out the problem.