Temp swings for SPS question.

[waverz]

I just setup mt 125 not too long ago and only had 2 400 watt MH's on each end, well today i got my 3rd 400 and lumenarc mini reflectors. The temp shot up to 82 in about 1/2 an hour and is staying there. Will i be able to get away with going from 79.-82 everyday or do i need to figure out a solution to make the heat from the lights go away?

What do you guys think?

[JB NY]

IME, That's not that bad, I'd try for a 2 degree difference, but nothing bad should happen with 3 degrees.

[BraenDead]

I'm going from 79 to 85 right now and have no problem, actually growth has increased a bit. As long as everything else is stable, I think you will be fine. If you run into other problems, the temp swing will only make them worse.

Bob

[waverz]

Thats good to hear, i have spent waaay to much money on this tank and really don't want to have to buy a chiller. I am so lucky to have a cold basement where the sump is, i think that is the only reason my temp isn't higher.

[waverz]

I think i am going to lower my baseline temp to 77, then when the lights come on it should only heat it up to 80. Worth a shot i guess. We'll see what happens tomorrow.

[RichConley]

Temp is a wierd one.


Basically, the more stable your temperature is, the less your corals are able to deal with temperature swings.

IE, if you keep it at 79 all year, your corals will start to bleach at 84. If you swing back and forth from 77-81 on a daily basis, your corals wont start bleaching till almost 90.


Theres nothing natural, or healthy about stable temperature.

[ReefWreak]

Before I switched controllers I let my tank go from 80-83 so if something bad happened with heat, the corals wouldn't bleach, like Rich said.

To be honest I don't think that if you start your tank at 77 it'll only raise those 4 degrees. I tried that in a tank, but the tank would still get to the same temp as before, just swing a lot more. The more stable you keep it, the better, even if the overall baseline is higher to the red zone

[mr pink floyd]

on some nights, ill have an oscillating fan in my room, along with the AC in the family room. Fan hits the tank, woke up to the tank at 76.5 once or twice, sometimes if its humid, the tank will reach up to 83-84 while im out, never had problems from it

of course this is very rare, usually im 79-82 in the summer, 78-81 winter

[waverz]

Cool thanks for the help guys.

[Wazzel]

My tank swings between 79 and 83 during the summer. During the winter between 78 and 81.

[Nanook]

Do you have a back-up plan, ie fans, controller to shut off lights if tank reaches "x" degrees, chiller, AC unit?

[samsfishnchips]

waverz,

as other have point it out, that range its fine,

but I really like how "JB NY" put it in another thread, you want to be a the lower end, not because its better, but because if things go wrong, you have some space to work with,

good luck,

sam

[RichConley]

Originally posted by samsfishnchips
waverz,

as other have point it out, that range its fine,

but I really like how "JB NY" put it in another thread, you want to be a the lower end, not because its better, but because if things go wrong, you have some space to work with,

good luck,

sam

yes, no, maybe.


The lower you run, the lower temperature your corals will bleach at.

[waverz]

I do have an ACII, i think i will have it shut off the MH's if it gets 83.

[stony_corals]

Yeah, temperature swings don't really matter much, it happens in the wild all the time. A couple things though, be mindful that as temps increase, so does the dissolved oxygen (and CO2 for that matter), so your fish may become somewhat stressed, and second, there is an upper limit, at around 91F+(33-35 C) degrees corals bleach period....

I've hit 87 a few times, no biggie...

[RichConley]

Originally posted by stony_corals
YA couple things though, be mindful that as temps increase, so does the dissolved oxygen (and CO2 for that matter),

Dissolved O2 actually decreased as temperature goes up, but with the ranges we're talking about, the decrease is small enough to not really be relevant.

[stony_corals]

That's what I meant thanks for catching that... It may not be with a light bioload.

[trey007]

I have been following this thread. I have the same problem swings 79-82 daily. I also have an Aquacontroller. Do you know how to set it up to turn off at say 83 without coming back on until the next day? I had my turning off at 83 but then they would come back on when it hit 82??

[RichConley]

Originally posted by stony_corals
That's what I meant thanks for catching that... It may not be with a light bioload.

IIRC, the difference in oxygen saturation at 75' and 85' is like 3%, so basically, it doesnt make a difference. If you're losing fish, you'd be losing them at the lower temp too.

[Denadai]

Originally posted by RichConley
yes, no, maybe.


The lower you run, the lower temperature your corals will bleach at.

I never read nothing about that

Dou you have some serious research or article about that ?

Regards

[RichConley]

Here's an article from Shimek. If you want more info, read some of the stuff he cites in the article

http://www.reefland.com/rho/1105/reefc7.php

[RichConley]

For those of you who think temperature stability is natural, heres the marshall islands (29C is 85F)



and Fiji

[manderx]

got any graphs for swings throughout the day?

[Denadai]

Originally posted by RichConley
Here's an article from Shimek. If you want more info, read some of the stuff he cites in the article

http://www.reefland.com/rho/1105/reefc7.php

The lower you run, the lower temperature your corals will bleach at.

I read the article....nothing about bleaching

[RichConley]

Originally posted by manderx
got any graphs for swings throughout the day?

Figure 2. Hourly sea surface temperatures taken 0.5 m below the lowest low water on a shallow coral reef in Pulau Pari, Indonesia, for January 1995 (modified from Fig. 4.3 in Wood, 1999). The red line indicates the maximum temperature, the blue line indicates the minimum temperature, and the pink bar indicates the zone of the average temperature, all values on the left ordinate. For comparison, the values in blue, on the right ordinate, are taken from shallow waters off the Washington coast in the Northeastern Pacific for the same period (values from this NOAA website), the blue band indicates the range of variation seen in that region. Note the range of variation between the highest and the lowest temperature is far greater over the coral reef area than in the offshore area of the Northeastern Pacific. All temperatures in degrees Celsius.

Coral reef temperatures are variable on tidal, diurnal, weekly, monthly, seasonally, annually, and multiannular time scales and the scope of variation is quite large (Figure 3). Generally, variations of 1.5 ºC to 4.5 ºC (2.7 ºF to 8.1 ºF) are common in equatorial areas, and one-day extremes such as a tidal pool on the Great Barrier Reef of 25.3 ºC to 34.9 ºC (77.5 ºF to 94.8 ºF) are not uncommon (Wood, 1999). Long-term fluctuations in the monthly average sea surface temperature at equatorial localities often fluctuate over a 3ºC to 5 ºC (5.4ºF to 9ºF) range (See Figure 3). When the data for the monthly average fluctuates this much it should be understood that the values for the daily extreme temperatures fluctuate over a much high range. It is worth remembering, that as far as oceanographers and climatologists are concerned, the “sea surface” implied in the measurement of Sea Surface Temperatures (SST) extends to a depth of about 50 m (165 feet) throughout most of the tropics.

Denedai, read the cited papers. All the info is in there. Corals produce stress responses at temperatures directly related to the temperatures they are normally exposed to. Bleaching is a stress response.