Temperature swings in a reef tank

[Wryknow]

Okay, I got my first large reef tank a couple of weeks ago and now I'm realizing that controlling temperature is not quite as straight-forward as I imagined. Mine seems to swing from 79- 82 degrees pretty regulalry and it has gotten as hot as 83.2 and as low as 78. The bigger tank stores a lot of heat and any temperature changes have a lot of momentum and take time to turn around.

My question for the forum is what type of temperature ranges and swings do you have in your tanks? I saw the tank temp poll and it indicated that my base settings are in the fairly normal range but what is acceptable variation? I eventually plan on having a Heteractus Magnifica in the tank.

 

[Travis L. Stevens]

My tank stays almost constant at 80*F. If you don't already, it might help to have two or more heaters instead of one. It sounds like your heaters aren't keeping up with things when the tank starts to cool off. It might take a little time with adjusting the heater(s)'s temperature setting to get it just right. Also, are you having a problem with cooling? How well does your canopy cope with heat from lighting? How about your sump? Do you run a chiller (I assume not)?

All in all, your tank isn't too bad. Those swings are rather large but not necessarily uncommon in some biotopes. But aiming to keep it as constant as possible would greatly help any of your current tank mates and future residents.

 

[Wryknow]

Yeah, it's definitely more of a swing than I would like. I am going to add another heater and that should take care of the low-end swings a bit.

I am running 8 x T5s in the canopy put I also have four ICECAP fans and the air inside stays pretty comfortable. I don't notice a big difference when I stick my hand in the back of the tank.

No chiller at this point, but I think that the ambient temperature is playing a significant role right now. I haven't kicked on the central AC yet so the house is getting a bit warm in the afternoon. Knocking 4 or 5 degrees off of the ambient temperature might make a difference on the high end.

I'm just trying to figure out how big of a problem this really is before I invest in too much additional equipment.

 

[Anemonebuff]

A 2-3 degree swing over a day(not quickly) will be acceptable. I would strive for the most constant temp you could get. Inshore fishes and inverts can withstand larger swings than deeper water critters.

 

[jeffbrig]

My tank runs 80-81 all the time. No heaters (other than the lights and pumps), and no fans. Just a chiller that comes on at 81. It cycles on a few times during the day when the lights are on.

 

[atillathetom]

77.5ish to 81ish

77.5ish to 81ish

I see a swing from the mid 77s to 81 or so over the course of the year, but daily it only goes up or down about 1.5degrees. It has been this way for 2.5 years and everything seems to be doing well. I have read over and over again that as long as the change is gradual...things should be OK.

That said, some reef central members insist that temp swings are the devil.

Tom

 

[davidryder]

temerature stability is more important than actual temp. keep your heater set at 82 if that's the highest it will ever reach. i would actually advise getting a chiller to keep it closer to 80, though. it's just a success rate factor, not a life or death situation. you should be ok with a 3 degree daily swing but things will do better (over time) with a more stable temp

 

[Wryknow]

Thanks for the input. I'm also going to try and play with the lighting cycle times a bit.

 

[joeychitwood]

Even nature is not without fluctuations. When diving, I've noticed temp swings of up to five degrees on the same reef from day to day depending on winds, currents, etc.