Rule of thumb for even needing a heater ?

[Guppy777]

Didnt plug in my heaters this past winter and guppies, snails and cherry shrimp are thriving . Tanks are not near windows and temps ranged from 75-69f . Mostly only got to 69 in the early morning for a few hours at the most. Been catching some heat being told that temps need to be constant at all times. Comments ?

 

[ppate1977]

I don't have a heater in my 10 gallon. It stays between 75-77 f EVERYDAY.

6 degree is not a huge swing unless it's happening in 24 hours IMO. Of course certain species need a more consistent and warmer temp than you have, but not your stock. I think you're fine.

 

[BigManAquatics]

Is 69 the room temp or the tank temp?

 

[ruud]

I believe most animals we keep in our tanks benefit from daily and seasonal fluctuations. The few studies that have been conducted actually show this.

The rule of thumb is simply investigate where wildtypes hail from and find out what temps and fluctuations occur.

I believe angelfish (but I'm not an expert of these fish), require relatively higher temps and relatively small amplitudes. A Dario myanmar (my expertise), on the other hand, can be kept below 60 F during winter nights and over 77F during summer days.

I keep cherry shrimp in all my Dario tanks and they are obviously exposed to the same temps. They don't breed in winter, until spring kicks in.

The big downside of heaters in general is that temps are kept fairly constant and in most cases too high (breeding temps). Most fish would benefit if the owner adjust the temp according to the seasons.

 

[SparkyJones]

mine sits year round at 76F at the lowest to 79 at the highest, and if the power were to go out I can get to 90F without the central AC.... but anyways, I use a heater because there's times I want 82F for the fish.

they have their uses for spawning or fish growing as juveniles, where you want them running a fast metabolism and eating a lot. but no, if your water stays within good range, you don't need to run a heater.

 

[Guppy777]

Is 69 the room temp or the tank temp?

Tank temp and yes when it gets really cold (below zero) it can swing 6 degrees in 24 hours. Plus in the summer it will be near 75 but closer to 80 when we get 100+ degrees.

 

[shrimpscaper]

I have no heaters in my tanks that have guppies and shrimp. I live in the northeast so the tanks also go around 69 in the winter. A lot of people just heat the room if they keep room temps 68+

 

[ProudPapa]

Didnt plug in my heaters this past winter and guppies, snails and cherry shrimp are thriving . Tanks are not near windows and temps ranged from 75-69f . Mostly only got to 69 in the early morning for a few hours at the most. Been catching some heat being told that temps need to be constant at all times. Comments ?

Temperatures aren't constant for wild aquatic creatures so I don't understand why people think the ones we keep in tanks need it. I also have guppies, snails, and shrimp in un-heated tanks. In winter my room temperature gets down to 60° F with no obvious ill effects.

I have shrimp thriving in tubs outside that were iced over for about two days this past winter (don't try that with guppies though, but goldfish would be fine).

 

[jinjerJOSH22]

Temperatures aren't constant for wild aquatic creatures so I don't understand why people think the ones we keep in tanks need it. I also have guppies, snails, and shrimp in un-heated tanks. In winter my room temperature gets down to 60° F with no obvious ill effects.

I have shrimp thriving in tubs outside that were iced over for about two days this past winter (don't try that with guppies though, but goldfish would be fine).

Agree here.
What is an issue is when there is a very sudden and sharp raise or drop in temperature. This will shock the fishes system causing to stop working properly which can kill.
Edited to add: Keep in mind aquaria are much smaller bodies of water which means temperature can change much more suddenly. Though spread out over the course of a day it shouldn't be a issue.