Tank Temps: How warm is too warm for your saltwater reef aquarium?

[RMS18]

Tank is 80.5-81.5. Lower at night higher during the day due to t5's.

I used to run lower but the t5 would create to large of a swing from day to night. So I just raised it. I think stability is better than number chasing.

 

[LordJoshaeus]

I am no expert, of course, but if I ever keep a reef again I want to shoot for the low 80's fahrenheit...reportedly dinoflagellates (the endless scourge of my previous saltwater tanks) do not do as well at temperatures above 80 (of course, this would be combined with better husbandry practices). I haven't given thought to the issue of cooling the tank in summer yet...since my current freshwater tanks are regularly hitting the low 80's during the summer even minus a heater, that issue would probably come up.

 

[FishTruck]

I try to keep it at 80 or below.... I think it is hard on some of the snails and fish and shortens the lifespan at the extremes of temp - just based on anecdotes. I am using a window unit in my fish room to keep the fish room at 72... but... then it's harder to keep the relative humidity below 50%. 74 seems to work better for humidity control... but... then the tank temps start to creep up to 81 degrees. Still working it out. I built plywood sumps and frag tanks, which also make it harder for the tank to cool off compared to glass.

The good news is that I can keep the tank warm in the winter pretty easily.

 

[adobo]

How do you people with central AC afford the electricity?

 

[Vegareef]

Those tank temps keeping rising as the summer gets closer and closer! When should you take action to reduce the heat and when is higher temps too high?

Let's talk about it today!

1. How high will you allow your tank temperature to rise before you take action? What's the MAX?

2. What do you do to keep temps down or help keep them lower during the warmer months?


Photo via @cedwards04

My tank stays between 77 and 79 in my central AC home. Anything higher and my snails will start to freak out being they like colder waters. Thanks to my homes AC, my tank doesn’t get any higher than 79. If it did go any higher, I would break out the fans I have reserved for such a problem.

 

[Fishnchips]

I don't get concerned until it hits 82, but it is almost always between 78 and 80.

 

[adobo]

I'm just going to put this out there:

There are plenty of reefs in the world where the water hits 94 degrees every day at low tide, and it doesn't seem to do any harm.

That said, I suppose it's a fair assumption that the species in those zones are a lot tougher than others.

I am tempted to say that it probably matters less whether you keep your tank at 76 degrees vs. 86 degrees and matters more that there is minimal swing in the temperature through the course of the day.

But then thinking about it more, even in the tropics, they have thermoclines. I suspect many of the organisms in reef tanks have been subjected to rapid water temperature changes in their natural habitats.

 

[Daniel92481]

On average, it stays between 77-79. I would start to freak out if it was over 80. Even here in Texas, so far no problems keeping it within range. If it was ever over 80, I would probably put a frozen water bottle in to slow things down a bit! No global warming happening here.

 

[Doctorgori]

I got Seahorses in one tank: its whatever the basement is (usually low 70’s all year)
My reef Tank is heated: 77-78F .... However in AZ my tanks were unheated all year also and 84-85 seems to be the magic upper limit before things get dicey; IME (I’d not argue with anyone with other temps tho)

 

[lefkonj]

How do you people with central AC afford the electricity?

It is all relative. I have a 180 gallon tank with a lot more invested into it than I am paying for the electricity, but I also have solar panels to help with the costs so it really depends.

 

[Ben Pedersen]

According to the NOOA scientists, "Reef-building corals cannot tolerate water temperatures below 64° Fahrenheit (18° Celsius). Many grow optimally in water temperatures between 73° and 84° Fahrenheit (23°–29°Celsius), but some can tolerate temperatures as high as 104° Fahrenheit (40° Celsius) for short periods."

So the extreme temperature range of reef building corals is 64° - 104°. Who would of guessed that some corals could handle 104° for short periods? Thats coral soup temperatures.

In nature water temperatures can swing more than 10° in a day, even in several hours. This can happen as a result of radiant heating of surface water layers from the sun. Quick cooling can occur due to upwelling and storm events.

Coral is very resilent to temperature and temperature changes, however, a stressed coral can bleach at 79°.

 

[WallysWorld]

Those tank temps keeping rising as the summer gets closer and closer! When should you take action to reduce the heat and when is higher temps too high?

Let's talk about it today!

1. How high will you allow your tank temperature to rise before you take action? What's the MAX?

2. What do you do to keep temps down or help keep them lower during the warmer months?


Photo via @cedwards04

I really hope that people aren't using a IR gun to measure tank temps accurately! They measure IR energy from all sources they are pointed and focused on (Transmitted Energy, Reflected Energy and Emitted Energy). Because it is focused on glass there are very high components of energy that are reflected and transmitted relative to the emitted energy. The emitted energy is what you want to measure. I'd be very surprised if the accuracy of this measurement is better than ±5°F, so in the image above the true tank temp could be 79°F to 89°F easily. In my opinion dipping my finger in the water would just as accurate!

FYI if you want to improve the measurement above, stick a black *not* shiny label on the glass, that is 5 to 6 inches in diameter, point the IR gun at the label from at least 18 inches out. Assuming that the label is at the temperature of the glass, you should get a better measurement of the glass temperature.

 

[Reesj]

29C or 84F.
I use a chiller but unfortunetely it is a bit underpowered and have to sit next to the tank. So during sumemr time it is set to 28C(82.4) and at 27C(80.6) during rest of the time. Ofc it creeps up +1C befroe it starts to cool off .

PS:I seriously am worried for people with open top tanks blowing fans at their tanks. Your electronic equipments and everything metal, gona corrode away so fast....

 

[cednet]

Mine doesn't get any higher than about 79 and I live in Phoenix. It's currently 109 outside. My AC stays around 77. When I top off from evaporation I add RO/DI ice cubes to the sump.

 

[Pascal Trill]

I just turn down my heaters a couple of degrees or turn 1 off for the summer

 

[Reefs and Geeks]

How do you people with central AC afford the electricity?

Raman noodles for lunch

 

[Scott71]

How do you people with central AC afford the electricity?

it’s not bad. I keep my house at 72. Elec bill runs $100-$250 per month depending on how hot/cold it is. Aquarium has no affect on house temp. I have a small house (1400 sq ft) so bigger houses run $250-$350.

 

[ThePurple12]

82-84 degrees. Everything's healthy, and I would assume that higher temperature=faster metabolism=faster growth.

 

[Sailfin11]

At one point my tank was running at 84 degrees because of a faulty heater. Everything besides my euphillya did ok. I believe they are more susceptible to high temps. Currently run at 80 degrees

 

[Cherub]

I forget people deal with these temperature issues in other places. Here in Colorado, my water is always just right. My heater works year round and I've never needed a chiller. Some people with MH do I suppose.