Does temperature really matter that much?

[Ferret_Friend]

Ok... I know everyone says you should have a heater to keep your tropical fishwater from fluctuating much, but what's the harm of the water changing 2-3 degrees between night and day, or 4-5 degrees depending on if the windows in your home are open or not?

I ask, because it just baffles me. These fish are more than capable of living in the wild, and in the wild, temperatures fluctuate daily and seasonally. So why is it exactly that having such a steady temperature is important?

I set up a 29 gallon about 10 days ago and put my last two painted tetras in to act as starter fish for the tank. Since I don't have a heater for it, I've been watching the temps. In that 10 day period, we peaked at 78, and today has been the lowest because it was in the 60's outside and I left the windows open. Even so, it was only 74 today and it was 75 or 76 yesterday.

I honestly wonder why temperature is that big a deal for these fish? The more I think about it, the less sense I can make of it. Sure, I can understand that a 10 degree change in one day is bad, but 1-2 degrees in the course of 24 hours or a 1-2 degree fluctuation between night and day doesn't seem like all that big a deal to me.

Why does it matter?

 

[Speakerman]

I have around an 8-12 degree change on my tanks without heaters. It's hot during the day and drops down very cold at night.

70 night
80 day

 

[Devilishturtles]

Basically it doesn't matter. A 3-5 degree change in a day is normal. Not having an adequate heater however, can cause temperature flucuations of more than 10 degrees a day, and that's not best for the fish. Why? It's just stressful and can be the cause of disease in alot of fish. Some are hardier than others and can handle it better too.

 

[JeffreyL]

temp

Yes, the water tropical fish live in will vary quite a bit in temperature. But, if it becomes stressful for the fish ..... they leave. Go to a cooler or warmer area. This way they can stay in an optium temp range. If they are unable to do this, the may grow lethargic, stop feeding, become ill or even die. It happens a lot in the wild.

In a tank they cannot of course leave, so they may get stressed if the temp is too high, too low or changes too quickly. That is why a heater is recomended. Since the tank is usually a few degrees above what our houses are, all is cool. So to speak.

And yes, if the temp swing is mild, you will be okay. But one swing of say, 10 degrees, and a lot of fish will suffer.

 

[jcarlilesiu]

Keep in mind that fish are cold blooded. Their body tempeture is much more important than it is in warm blooded mamals, and their ability to adapt to quick temperature changes is lower.

In a large body of water, temperature is much more stable than you think. Down deep, typically cold, up top, heated by the sun. the ability to move up and down in this body to maintain a temperature or at least a slower change in temperature is important.

In our small aquariums, they don't have the flexibility to move to different positions in the water to attain a stable temperature. Its all or nothing, and the tank temps shifts do put an incredible amount of additional stress on them. A heater will help to stabilize the temperature and is important in this type of small water set-up

 

[Ferret_Friend]

I suppse this problem is gone anyhow. I found a free 100w heater. w00!