are temperature swing bad for a reef tank

[dmirza]

I am thinking of having a multi teered cooling system. I.e. the temp is normally 79 then when it hits 83 the fans come on and when it hits 86 the chiller comes on. Would t his be bad for the fish.

I have a 90 gallon tank and will be using two 175 Watt MH bulbs, so the temp swing should not be too fast.

[SeanT]

How is it that you have the same avatar as SkinyChinaMan?
What are the odds lol?

http://archive.reefcentral.com/forums/showthread.php?s=&threadid=640719

[superedge88]

I would have the fan come on at about 81 degrees, and the chiller come on at 83.

[dmirza]

haha, yeah I stole the avatar from somebody. It looks really cool. Probably was skinny china man

[NicoleC]

A temp swing that large is extremely unnatural for a reef. If it were me (and I do this myself), I would keep the temp at a base of 80, run fans all the time when it's warm inside the house, and have the chiller set at 83 with a 1 degree variance. (IE, when it hits 83, the chiller runs until it drops the temp to 82... then repeat).

3 degrees F is not as stressful, but it's still not normal for most of our inhabitants.

I think you will be surprised how effective fans are. If you can get airspace around the tank, that will also help. On really hot days, I would keep the doors of my stand open for additional ventilation, which was usually 1 or 2 degrees right there since I have a couple of open feet behind the tank, too.

[dmirza]

thanks, that makes sence. I think I read Anthony (I could be wrong here) saying that temp swings are not bad for a tank. Also, while scuba diving in Monterey, CA (freezing by the way) I did find pockets of warm water, so I assumed temp swings in marine life are not very stressful for the inhabitants.

[SEAFLOWERS]

I have read that temp. swings as little as two degrees can cause bleaching events in some corals. best to keep tank temp as constant as possible between 75 to 80 degrees.

[Triterium]

My tank starts the day at 70-72 and ends at 78-82, depending on outdoor conditions. I dont think this type of a swing is a problem for most reef fishes. I also have many corals in the tank (SPS, LPS, etc) They all look good but don't grow as well as those kept in my indoor tanks. Ive had one of my tanks get to about 90 degrees and nothing looked bothered at all. It all comes down to what you are keeping and what kind of growth you want. I bet you would get better growth in some corals with stable temperature. But who knows, many reefs experience daily temperature fluctuations and the swings may be beneficial to some corals.

[stevedola]

Originally posted by Triterium
My tank starts the day at 70-72 and ends at 78-82, depending on outdoor conditions. I dont think this type of a swing is a problem for most reef fishes. I also have many corals in the tank (SPS, LPS, etc) They all look good but don't grow as well as those kept in my indoor tanks. Ive had one of my tanks get to about 90 degrees and nothing looked bothered at all. It all comes down to what you are keeping and what kind of growth you want. I bet you would get better growth in some corals with stable temperature. But who knows, many reefs experience daily temperature fluctuations and the swings may be beneficial to some corals.

Actually there has been research done to prove that swings that large do not happen naturally on a coral reef and it is not healthy for inhabitants. Higher temperatures stress fish and corals to points that threaten their existance. Fish respirate faster and it shortens their lives. PH swings when temperature fluctuates which definately stress many type of corals especially SPS. I have expirenced a temp swing from 79 to 86 that bleached 2 sps colonies. Just because softies and some lps survive large temp swings doesnt mean it is beneficial. On the contrary, it is detrimental to the long term success of our aquariums.

[Triterium]

Originally posted by stevedola
Actually there has been research done to prove that swings that large do not happen naturally on a coral reef and it is not healthy for inhabitants.
hmmm i haven't heard this... are you sure your source was accurate? This is what Dr. Ron wrote in an earlier thread....

"Temperature swings are probably absolutely necessary for normal behavior of some of the reef animals. In general, the temps on a normal reef fluctuate at least 10 deg F. per day, and there is no problem at all with our tanks fluctuating this much.

The greatest fluctation that I have come across for natural coral reefs, and there may be greater ones was a swing from 68 deg F to 92 deg. F on the reef flats of Johnston Atoll. This is a high latitude reef with a reduced number of species, undoubtedly due to both the low and the high ends. Nonetheless, it still was (and is ) a good coral reef"

Higher temperatures stress fish and corals to points that threaten their existance. Fish respirate faster and it shortens their lives.
Well this really depends on the animal. Tide pools can have 30+ degree daily temperature fluctuation. Shallow lagoons can easily reach 90+ degrees.

PH swings when temperature fluctuates which definately stress many type of corals especially SPS
This is definately true and in our small systems pH swings can be very high. This may be why temperature swings are more detrimental in aquariums compared to reefs.

I have expirenced a temp swing from 79 to 86 that bleached 2 sps colonies. Just because softies and some lps survive large temp swings doesnt mean it is beneficial. On the contrary, it is detrimental to the long term success of our aquariums.

Very good point. Many corals come from reefs that experience very small temperature changes. Not all reefs are the same. Some are shallow, some are deep, some have stable temperatures, others do not. Most reef keepers have no idea what type of condintions the coral was collected from. Some corals may do better at 72 degrees, others at 88 degrees. Like i said in my previous post, it all comes down to what you are keeping and what kind of growth you want.

My tank experiences 7-10 degree temperature fluctuations daily. I have a lot of fish in it including a 3-foot moray. I also have acros, montiporas, LPS and many others. All are doing well but like i said, they are not doing nearly as well as they could. :rollface:

[dmirza]

thanks for the help. I thought I read something about temp swings not being bad for a reef tank on this forum, but I wasn't sure.

[stevedola]

For the most part we arent talking about tide pool inhabitants or animals from the johnston atoll. Those animals have evolved over milleniums where as most of our tank's creatures are used to a steady temperature or temp swings that are slow and gradual.

Increased temp does impact coral growth and can lead to bleaching. see www.reefbase.org--->
The unusual high and sustained sea surface temperatures (28-31°C---83°- 88°F) from January to April of 2000 have caused massive coral bleaching of major reefs on Viti Levu, Vanua Levu , Taveuni, Ovalau and Kadavu. The extent of the damage to Fiji’s coral reefs is not known and will have serious impacts on Fiji’s reefs. Reefs that have been degraded with pollution will be the most affected.
Source: Vuki, V., M. Naqasima and R. Vave , 2000, Status of Fiji's Coral Reefs. Global Coral Reef Monitoring Network (GCRMN) Report.

So if naturally occuring coral reefs expirence massive bleaching from unnatural temp swings and elevated temperatures then why would our small ecosystems be any different.

You are correct about it depending upon the different species of animals. Some animals adapt quickly to temperature and water quality alterations where as others simply do not. Some particular species have a higher tolerance for temp just like land based animals. However, i do not believe that large fluctuations (daily) are healthy for any of the species we as reefers intend to keep. Sustaining life and thriving are two totally different things and by consistantly altering temperature with large deviations I think you impead the animal's ability to thrive.

[Triterium]

read this quote from Dr. Ron again... he is not talking about tidepool or high-latitude reefs, he is talking about a "normal reef"

Temperature swings are probably absolutely necessary for normal behavior of some of the reef animals. In general, the temps on a normal reef fluctuate at least 10 deg F. per day, and there is no problem at all with our tanks fluctuating this much


So if naturally occuring coral reefs expirence massive bleaching from unnatural temp swings and elevated temperatures then why would our small ecosystems be any different.

So which one is it? Is it the temperature swings or the elevated tempertare or both? I believe scientist think it is caused by a net increase in water temperature, and has nothing to do with daily temperature fluctuation - the topic of this thread.

Very good points though and i think this thread has presented a lot of useful information :D

[stevedola]

I guess we will have to agree to disagree. I dont see the reason to pursue this topic further. I will continue to maintain 78-80 and you continue with your procedures. You must feel comfortable allowing your tank to swing 10 degrees and reach elevated temp levels. I however have had bad expirences with temp swings and temp peaks of 86 degrees never mind 90. At some point you have to make your own conjectures about subjects---that is what I have done.

[porky]

If you have ever dove on real coral reef you would know that daily temp swings in the 10+ degree relm are the norm. Temp can vary dramatically from midday highs to night time lows...

[stevedola]

Triterium

From what i read in that article/publication they thought that the problem was due to the higher than normal temp from Elnino. They felt that the extremes were too much for the corals to handle.

Porky

I have dove on reefs in the grand caymens and megan bay and do know that in general reef's temp fluctuate daily. I wasnt refering to swings in a normal temp range (ie 74-84) I was refering to extreme temp fluctuations when they reach upwards of 87-90+. Triterium had stated that his tank had reached 90 with no ill effects and suggested that it could be beneficial for certain corals. I didnt believe that to be true so I replied.

Porky, do you encourage your tank to swing 10 degrees daily??

[porky]

I wasnt refering to swings in a normal temp range (ie 74-84) I was refering to extreme temp fluctuations when they reach upwards of 87-90+.
Oh okay I agree 100% then... extreme temperatures, one way or the other, is not good.

Triterium had stated that his tank had reached 90 with no ill effects and suggested that it could be beneficial for certain corals. I didnt believe that to be true so I replied.
Yep I agree again, temperate extremes should be avoided and would be deleterious if the coral is kept out of it's normal temperate zone for too long.

Porky, do you encourage your tank to swing 10 degrees daily??
No, but sometimes it happens, especially this time of year. The fall weather in Ohio is some of the best in the country. Midday highs in the 70's-80's make recreation really comfortable and night time lows in the 50's makes for really good sleeping weather... Anywho, my tank sits in the basement and most of the time I keep a window open by the tank. Midday with the halides on the tank temp. will get above 80, by the middle of the night the tank temp. has dropped to the low 70's. But at no time are the corals outside of thier natural temperate zone, so no biggie as far as I'm concerned. Now if my tank was getting in the 90's (or below 70 on the other end) on a regular basis I would be more concerned.

[Triterium]

i actually dont have a choice on my tank's temperature. Its in a greenhouse and is heated by the sun during the day and a natural gas air heater at night. Inside air temperature reaches 100 degrees on a sunny day even during winter. If i had a choice i would keep the tank at about 78 with no swings. :D If I was worried about the swings, i wouldn't have just bought a $300 fish :P

[porky]

Inside air temperature reaches 100 degrees on a sunny day even during winter.
:eek: OMG! Do you do anything to try and lower the temps or just go with the flow?

[Triterium]

Its been as hot as 120 degrees inside (recorded on several thermometers in the shade!). The water temperature stays under 83 degrees (even on the hottest days) thanks to a cheap fan blowing over the sump. Another reason i am able to keep it so low is the system has about 300+ gallons of water and i let the temperature drop to 70 degrees at night.... so it takes a lot to heat it up 13 degrees. During winter months the max water temperature is about 78 degrees with a min of 70.

The fish and coral do fine and appear very happy. On top of the temp swings i also used a DSB of locally collected sand, I used silica sand and garden soil with manure for the mangrove tank, have drift wood in the tank and add fertilizer to the water. ;) Oh and i use 50 degree water from the garden hose for top offs and to make water changes. I do have a 100GPD RO/DI filter but thats too much work.

[sihaya]

I find it really hard to keep my temp constant to <3 degrees. Mine goes from 81 to 84 over the course of the day. I don't think it's a problem for the corals I keep. As long as my pagado cup opens up every morning I figure everything is probably ok.