How stable should tank temp be? aka Do I need a heater?

[glb]

I have a 40g breeder and live in South Florida. Our A/C thermostat is set at 73F and the tank runs at about 77-79 degrees daily depending on whether or not the lights are on (T-5’s). Sometimes it will fluctuate 2.5-3 degrees in a day. Does this fluctuation matter? I’m thinking no, but wanted to check. I need to replace the heater I have for colder days. It probably gets used only 2-3 days a year when the room temp gets down to 70. I’m thinking leave it out of the tank for most of the year and only put it in when needed. Does this make sense? Do I need one at all? Thanks!!

 

[Cole.mormon]

Yes

 

[Cole.mormon]

Temp should be 78

 

[Cole.mormon]

Fluval M Submersible Heater

 

[xxkenny90xx]

77-79 is totally fine. My worry would be if you forget on those colder days. Best thing to do would be to put a heater in there with a temp controller. Hypothetically speaking the heater should almost never turn on if you set it up right.

Imo some temp fluctuation is actually a good thing

 

[Cole.mormon]

Id have to disagree

 

[xxkenny90xx]

Id have to disagree

And why is that?

 

[Ribo15]

Yes you need a heater. Stability in a saltwater tank is key. That includes temp.

 

[Cole.mormon]

BC ive had temp Felix before and lost a few fish it wavered about .5 fldegrees a day but that could have also been heater issues

 

[Ribo15]

.5 degree is not bad. 1 degree is acceptable. The 3 degrees is getting to be worrisome though.

 

[xxkenny90xx]

Yes you need a heater. Stability in a saltwater tank is key. That includes temp.

You know the oceans temp changes with the seasons right? Imo when we keep our Temps in too tight of a range we are setting our fish up for failure. Then when something goes wrong and the temp changes now you have an emergency. If it always slightly fluctuates then you have more wiggle room when something goes wrong and the temp changes significantly

BC ive had temp Felix before and lost a few fish it wavered about .5 fldegrees a day but that could have also been heater issues

.5 degrees absolutely will not hurt your fish. More likely your heater was damaged and leaking voltage

 

[xxkenny90xx]

.5 degree is not bad. 1 degree is acceptable. The 3 degrees is getting to be worrisome though.

I can more or less agree with that

 

[Miguel Negron]

77-79

 

[Cole.mormon]

+1 on 77 top 79

 

[Cole.mormon]

To

 

[xxkenny90xx]

75-82 is the range imo....

In general anyways, not for daily fluctuations

 

[Daddy-o]

I had read somewhere that most wild coral live within 5 degrees of their upper limit.

 

[Dom]

Install a heater.
Better to have it and not need it, than to need it and not have it.

 

[glb]

Thanks everyone! But if I install a heater to keep it around 78, won’t the tank still warm up a few degrees when the lights come on? I know the heater would be off during the day, but it seems that I would still have a range, just higher than the one I have now. Am I thinking about this wrong? I have an apex so I can program the heater no problem. I have a Cobalt heater that’s old and needs to be replaced. If I do get one, what range would you suggest for the programming?

 

[Ribo15]

Set it and 78 and then see how high the temperature gets during the day. It will be better than letting it swing as much as it will with no heater I’m sure