Temperature: the range and the 'acceptable' extremes

[tzylak]

My chiller goes ON at 79 and turns OFF at 77. I see that as the 'preferred' temperature. Also, the outlet for a heater on it turns ON at 76. So if the 'extreme' of high temperature is around 85F, what is the corresponding 'extreme' on the low side?? Mathematically, that would be around 71, but realistically, would the tank critters survive at that low of temperature??

My fish: Ocellaris Clown, B&W Clown, Firefish Goby, 6-Line Wrasse, Midas Blenny, 3 Banggai Cardinals, Cleaner Shrimp, Fire Shrimp, Banded Coral Shrimp, Peppermint Shrimp, Bristle Worms and CUC.
Reef: 150 lb. Sand, 70 lb. Rock, Frog Spawn, Button Polyps, Hammer, Mushrooms, Kenya Trees, Brain, Leather Toadstool, Cheato and one aiptasia
Tank: 50g hex with overflow, 23 gal sump with DSB, 2x Rio 3100 return pumps, 2x15" power compact 10K, 2x 50/50, 1x actinic, chiller 650, heater 150W, skimmer 65.

 

[nmotz]

I've read/heard that marine animals do better at the lower end of the temp scale than the higher end (metabolism/activity just slows down). One of the mods (Sk8r) just had to survive a prolonged power outage and the tank temp was in the 60s for several days. There were losses, but not everything was lost, and most of that was probably due to toxins/lack of oxygen as opposed to low temperature.

 

[hobbzz]

www.reefcentral.com/forums/showthread.php?t=1869167

 

[Sk8r]

I found that, in a power outage, deliberately driving the temperature down to 66.1 aided survival, because cold water can hold more oxygen than hot. 81 is, at the other end, too hot. 62 is the beginning of lethality for many species, however worms and mysis shrimp perished at 66. 81 is the beginning of trouble on the other end, and 85 is hot enough to bleach coralline under strong light. Floating bags of ice can lower temperature. So can a fan on the water surface. 79 is a pretty good temperature to hold.

 

[thegrun]

I have fans that start to kick in when the tank hits 80 and I have them all on at 81 degrees on the high end. I used to keep the low temperature at 78, but several local reefers I know with very nice tanks including two tank of the month recipients let their tanks drop to 75, so this past winter I also let my tank drop to 75 degrees. The only difference I noticed is that my clown fish lay eggs less frequently. All the corals (mixed reef SPS dominated) look great.

 

[kmbyrnes]

According to my logs, in 2 years I have seen a high of 84.1 and a low of 77. I don't have heater or a chiller. Just a fan added when I hit 84, which dropped the temp back to 80 within hours with zero loss. Overall my tanks stay 79.4 - 80.5 and everyone seems happy enough.

 

[Dundermifflin]

(thegrun) What is the device used to kick on fans automatically when the room reaches a specified temperature?

 

[shifty51008]

(thegrun) What is the device used to kick on fans automatically when the room reaches a specified temperature?

Any temp controller can do this along with apex or reef keeper. I have a ranco dual temp controller that controlls my heaters and fans however i dont use fans anymore.

 

[tzylak]

I thank you all for sharing.
Wow! I thought that 70s was the limit, now I see that the lower limit is at mid-60s.
I feel better now.
THANKS!