Reefs.org Forums

[jamesw]

One poster asked us to address why average coral reef temperatures might not be such a good idea in a closed system.

One reason may be that if these bacteria are more virulent at these temperatures than say 78f vs 82f, then the fact that our animals are contained in a VERY small box containing water with a VERY high concentration of bacteria (relative to coral reefs) might just be a problem. I believe one of our authors suggested methods for measuring numbers of bacteria in reef aquaria in a past column and I believe he also may have posted some results from various reef aquaria and coral reefs.

That's my 2 cents. Perhaps Charles Delbeek will contribute to this discussion as well.

My opinion (and that's all it is) on this matter is that I'd rather have my corals "slowly freezing" as one author put it - as opposed to quickly melting.

Cheers
James Wiseman

[saltshop]

One poster asked us to address why average coral reef temperatures might not be such a good idea in a closed system.

Oh crap! What do you think the odds are of this staying civilized? I guess it might have a chance since this is kind of an "off the beaten path forum".

One reason may be that if these bacteria are more virulent at these temperatures than say 78f vs 82f, then the fact that our animals are contained in a VERY small box containing water with a VERY high concentration of bacteria (relative to coral reefs) might just be a problem.

There are obviously many factors such as is the same bacterium responsible for virulence in different locations which bleach at different temperatures or could it be more than one bacterium, or even a different cause all together? Do these same bacteria exist long term in our tanks? Since it has been said the bacteria rapidly die off under cooler temperatures is it possible to eliminate them through a "cold-acclimation"?


I believe one of our authors suggested methods for measuring numbers of bacteria in reef aquaria in a past column and I believe he also may have posted some results from various reef aquaria and coral reefs.

There are some problems with the mentioned test in that it basically measures the multiplication rate and end point of the bacteria, not the species or even the start count. It would be quite useful in determining just how poluted your tank is though as the more nutrients the quicker the test will change colors as the bacteria rapidly multiply inside the vial. I do agree our tanks are virtual sewers though...just not sure of cause and effect. Is it the increased microbial community or the nutrients themselves that could cause problems, or both?

I think the biggest thing to mention might be the water flow issue. For the most part no matter how hard we try we just suck at providing anything close to normal circulation patterns in a tank. New items like the Reeftecs and Tunze should help somewhat. I really think trying to approach natural temperatures with unnatural water movement is highly responsible for many of the problems people report.

Despite what some may think from scuffles I have had with them before on this subject I do not think corals will die at somewhat decreased temps. in a tank. While it is true that temperature and correlates of temperature are extremely important to biogeography in the wild not all of these necessarily correspond to tank life. The big one that comes to mind is the overgrowth of algae in the wild at decreased temperatures..basically algae outcompetes the corals at lower temperatures. In a tank of course we can control who gets what space and it is rather easy to far exceed the number of grazers that would exist in the wild per sq. meter. One problem that I don't really see a way around is the change in carbonate saturation point at decreased temperatures. As temps. drop aragonite becomes more soluble creating a situation where more energy is actually needed for skeletogenesis with a corresponding decrease in metabolism for both zoo and host. It would be pretty similar to purposefully running your tank at a lower pH. Will increasing the Ca and CO3 levels beyond what is found in nature help to offset this...not sure?

FWIW, I keep my own tanks at 82 ish and open hoods at 84, but if you were to try to tell me temperature has no effect on biogeography I will fight you tooth and nail.

[AF Founder]

JB,

If you have a problem with something that I have said please address your concerns to me.

[saltshop]

JB,

If you have a problem with something that I have said please address your concerns to me.

No, nothing personal. If you are referring to the comment in the other thread that you are the one I have a bone to pick it was said partly in jest. Basically, the title of Charles Delbeek's article led me to believe that he was inferring a relationship between the Rosenberg article and the Catalaphyllia problems and apparently you picked the title. I then proceeded to get overemotional about the whole situation, typed in some things I now regret, and have since edited, and here we are. If you are referring to why this thread is here I did not expect it to be here...I just commented that maybe a discussion about why certain things might not hold true in a closed system might be more productive than the fact that Greg has a very nice tank so we should all do what he does from the editorial. It seems whenever this topic comes up it goes something like this "they will all die from stress" - "no they won't" - "yes they will" - "no......" and so on. The editorial seemed to be saying "see, no they won't" so I just thought it may be interesting to see what thoughts there were as to "why not", that is all.

[AF Founder]

JB,

If you have a problem with something that I have said please address your concerns to me.

No, nothing personal. If you are referring to the comment in the other thread that you are the one I have a bone to pick it was said partly in jest. Basically, the title of Charles Delbeek's article led me to believe that he was inferring a relationship between the Rosenberg article and the Catalaphyllia problems and apparently you picked the title. I then proceeded to get overemotional about the whole situation, typed in some things I now regret, and have since edited, and here we are. If you are referring to why this thread is here I did not expect it to be here...I just commented that maybe a discussion about why certain things might not hold true in a closed system might be more productive than the fact that Greg has a very nice tank so we should all do what he does from the editorial. It seems whenever this topic comes up it goes something like this "they will all die from stress" - "no they won't" - "yes they will" - "no......" and so on. The editorial seemed to be saying "see, no they won't" so I just thought it may be interesting to see what thoughts there were as to "why not", that is all.

JB,

What I said in the editorial, and have been saying for a long time is that my experience and that of other reef keepers is that Shimek is wrong about optimum temps for reef tanks, and that if new reef keepers followed his advice they probably would have RTM problems. In the absense of scientific evidence reef keepers need to follow the anecdotal experience of reef keepers who like myself have been successfully keeping corals for more than ten years. Of course, I'm well aware that anecdotal experience can be mistaken, but until the scientific community fully understands the mechanisms that lead to coral disease it is better than nothing, and certainly better than thoeries not based on long term husbandry experience with reef tanks. I also noted that some scientists seem to be finding a correlation between high temps. and disease. The final verdict is clearly not in yet.

[blade2run]

What temps do you guys keep your tanks at. Mine pretty much stays at 78 deg. without a chiller... Should it be lower or higher?

[AF Founder]

What temps do you guys keep your tanks at. Mine pretty much stays at 78 deg. without a chiller... Should it be lower or higher?

I would say that 78F is about ideal for a reef tank.

[mkirda]

I would say that 78F is about ideal for a reef tank.

I would say that anywhere from 78 to 85 is ideal for a reef tank.

I have a lot of respect for Ron Shimek. One thing I have noticed over the years is that he tends to like to take aim at a lot of 'established wisdom', and he does this by making a lot of bold-sounding statements. They are not exactly exaggerations, but he may over-state things in order to make a point.

The trouble with this is that in making what one of my local club members refers to as pronouncements, people tend to hear only the bold point, and not the advice that is behind it.

I have always known Ron to recommend temps between 82-85 degrees, and if you were currently keeping your tank at a lower temperature, the recommendation was to *slowly* raise the temp and watch for signs of stress.

For some reason, some people heard the pronouncement, ran out and cranked up their heaters, then had problems.

Is that Ron's fault?

Frankly, I would argue no. It is the aquarists for not listening well, paying attention, and following the advice as given.

I keep my tank on the warmer side- my current set-up is riding 85 at the moment. I will likely keep it a bit cooler soon- I generally shoot for 80-82 during the winter months.

Let me also make it clear that I am not a Shimek apologist. He and I do not see eye to eye on several reef topics, but we agree to disagree. But in the temperature debate, I tend towards 'Warmer is better', as long as your tank's inhabitants also agree. They are a much better judge than you or I can ever be.

Lastly, the work on virulence of bacteria in coral slime coats: It seems to me based on memory that the temps involved are higher than most people keep their tanks, even me. As I recall, this started to kick in at 86+ to 89 degrees, roughly corresponding to the beginning phases of bleaching. People keeping tanks at 85 need to be aware of this possibility, and be prepared to act accordingly. Water motion becomes more important at these temps, and using a prop-pump or similar system to provide adequate flow becomes essential, IMO.

Regards.
Mike Kirda

[AF Founder]

Mike,

I've been around reef keepers for a long time, and have seen what we call RTN make its appearance almost always during the high temperature months. There appears now clear evidence that RTN type bacteria reproduce most vigorously at higher temps. All of this is anecdotal, but so far there appears real consistency between high temp. and bacterial outbreaks. I'm not questioning the temperature that corals evolved in the wild, but that those temps. do not translate well when it comes to the confined space of a reef tank.

[fraggintime]

I have maintained sps for over 10 years and lps and softies for at least 15 years. I used to keep temps at 75-78 degrees and never had a problem. Fast growth, healty corals, long term. Now I keep temp at
82-84 for at least 1 year now with mostly sps,some lps and 1 or 2 softies
mushrooms gorgonians etc. NO PROBLEMS nice color,fast growth and great polyp extension etc..The only reason I raised temp is because of electricity bill . I actually feel(personal opinion only)that the corals look healthier at the higher temp..I might add that I have about 2800 gallons an hour going through my 265 gallon system plus I have another 1100gph on a surge system. I do believe that at any temp you need very good water flow but it is much more imperitive at higher temps.

There is no answer to this temperature question because we are all having success at many different temperature levels and because our systems are all fingerprints with not one being the same it is all speculation and can go on for ever. Pick a temp and go with it..

Just my unscientific opinion based on personal observation
Take care