Some of the rock is pretty new, some is old. I do have a problem with a lack of coralline....I cannot seem to keep up. I tested my water yesterday which showed my calcium at 385 and my alk at 8.6, today the calcium was the same.........not normal in my tank, the alk (like I said) went from 8.6 to 9.6. I DO know the kalk reactor is not going to keep me from adding supplement BUT hopefully will help some. Speaking of which I need to test my Mg. Thanks all for your thoughts...........I always appreciate new ideas!
Common Misconceptions In the Hobby
- Thread starter Peter Eichler
- Start date
E-A-G-L-E-S
New member
This is most likely the reason you are having swings AND are not growing coralline. Your Mag. is probabaly low.
Just tested at 1260. I added 75ml of Kents Tech M so it should be nearish 1300, I'll add some more tomorrow. I don't think this would cause a low alk problem though? My tank EATS calcium and alk like crazy....seeing a raise in alk without buffer makes me REALLY happy, and a steady calcium level is great too. I may add some calcium as well......which also contains magnesium so that should put me where I should be. Thanks again.
E-A-G-L-E-S
New member
No, low mag. will make it difficult to have stable Ca./Alk. params.
1300ppm is pretty good. I stay around 1320ppm. Anything in the 1300's is good - imo.
1300ppm is pretty good. I stay around 1320ppm. Anything in the 1300's is good - imo.
My least favorite misconception is that corals and reef aquaria are more "difficult" than fish-only tanks. I find the opposite to be true. The easiest coral is far easier than the easiest fish, at least with the modern equipment that is available.
More expensive? Perhaps. But not more difficult.
More expensive? Perhaps. But not more difficult.
E-A-G-L-E-S
New member
Well, on the other hand fish can handle nitrates and overall less ideal conditions better than at least most sps.
But that does work both ways. There are fish, like the batfish and others, that do take more care than many types of corals require.
But that does work both ways. There are fish, like the batfish and others, that do take more care than many types of corals require.
E-A-G-L-E-S
New member
Rynon....I think the spectrum of light from actinic lamps of 420nm or 460nm do aide in coralline growth but I'm definitely not sure.
aninjaatemyshoe
New member
I'll reference the issue about the disease tonight when I get home. Don't have access to it right now.
Peter, the article you referenced (and the follow-up article) is quite nice in outlining how the natural reef environment is not as "stable" as we tend to think. The second article also impresses that it is important for corals in their natural environment to have environmental variation, but more so with seasonal variation as upposed to day-to-day variation. However, it doesn't even go into the physiological or even practicle issues that separate the natural environment from the aquarium environment. It had very little in terms of reef aquarium husbandry, just the assumption that variations in temp, salinity, so forth must directly translate to the best husbandry practices for us. The article talks about evolution and adaption over long periods of change, but again this is not something we are experiencing in our little "pieces of the ocean." It does meantion that environmental variations are important for sexual reproduction, but how many of us are striving for that? If anything, sexual reproduction is what we want to prevent because we are not prepared to handle the explosion of free floating nutrients. And even if we wanted this outcome, the environmental cues would require even more equipment and control of conditions than we tend to use in our aquariums. I don't think it prepares a very convincing case in regards to reef keeping.
Peter, the article you referenced (and the follow-up article) is quite nice in outlining how the natural reef environment is not as "stable" as we tend to think. The second article also impresses that it is important for corals in their natural environment to have environmental variation, but more so with seasonal variation as upposed to day-to-day variation. However, it doesn't even go into the physiological or even practicle issues that separate the natural environment from the aquarium environment. It had very little in terms of reef aquarium husbandry, just the assumption that variations in temp, salinity, so forth must directly translate to the best husbandry practices for us. The article talks about evolution and adaption over long periods of change, but again this is not something we are experiencing in our little "pieces of the ocean." It does meantion that environmental variations are important for sexual reproduction, but how many of us are striving for that? If anything, sexual reproduction is what we want to prevent because we are not prepared to handle the explosion of free floating nutrients. And even if we wanted this outcome, the environmental cues would require even more equipment and control of conditions than we tend to use in our aquariums. I don't think it prepares a very convincing case in regards to reef keeping.
ManotheSea
New member
Here is one that I beleive to be a myth. Please correct me if you think im wrong.
MYTH: Using bagged "live"sand and bottled "live" bacteria cultures will shorten new tank cycles. When I first got into salt water many years ago, i couldnt understand how these could possibly be alive after months on a store shelf. It never made any sense to me but no one was complaining. Most RC member giving advice even suggested its use. Now I see things much more clearly. Store bagged sand is dead sand.
I now use fresh from the ocean live sand. A new tank will not even have a cycle using fresh sand. Fresh sand does not smell horribly like dead sand in a bag does after some tank time. Fresh sand will not have an algae bloom stage. The cycle and the algae bloom comes from dumping a 15 lb bag of dead crap into your tank. For those who do not have fresh sand access, I highly recommend finding some one who can overnight ship fresh live sand to you. Another great alternative is to use dry sand and seed it with cups of live sand taken from your fiends tanks. The use of real fresh live sand will greatly reduce the cycle and the algae bloom if not eliminate them. This holds true whether the fresh sand is from the ocean, an overnight delivery from the ocean direct or from your friends donations. I have seen acros put into new tanks after the second day with no ill affects using fresh sand and cured live rock.
MYTH: Using bagged "live"sand and bottled "live" bacteria cultures will shorten new tank cycles. When I first got into salt water many years ago, i couldnt understand how these could possibly be alive after months on a store shelf. It never made any sense to me but no one was complaining. Most RC member giving advice even suggested its use. Now I see things much more clearly. Store bagged sand is dead sand.
I now use fresh from the ocean live sand. A new tank will not even have a cycle using fresh sand. Fresh sand does not smell horribly like dead sand in a bag does after some tank time. Fresh sand will not have an algae bloom stage. The cycle and the algae bloom comes from dumping a 15 lb bag of dead crap into your tank. For those who do not have fresh sand access, I highly recommend finding some one who can overnight ship fresh live sand to you. Another great alternative is to use dry sand and seed it with cups of live sand taken from your fiends tanks. The use of real fresh live sand will greatly reduce the cycle and the algae bloom if not eliminate them. This holds true whether the fresh sand is from the ocean, an overnight delivery from the ocean direct or from your friends donations. I have seen acros put into new tanks after the second day with no ill affects using fresh sand and cured live rock.
Peter Eichler
New member
Ok, but can you come up with a strong argument to support keeping aquariums lower in temperature with extremely consisten temperature conditions? The only reason those things are stressed now is because many years ago someone started spouting off about how stable reef conditions are so we should keep our aquariums stable. I agree that we need to adjust some of our procedures to better suit home aquaria. However, the old suggestions of keeping temps below 80 and always keeping them stable holds little weight, even when you consider the differences between the reef and out aquariums. Lastly, we should be striving for spawning events. If we can find a way to replicate them it would be a great advance in this hobby. Until then spawning events are not so common in aquariums that maintain higher water temps to warrant not trying better to replicate natural conditions.
aninjaatemyshoe
New member
Ok, my references all come from the Reef Aquarium V. 3 (Delbeek and Sprung), which is a great in-depth source. For the purposes of trying to keep this somewhat brief, I have skipped some things and tried to hit the major points.
I didn't notice at first, but it actually references the Shimek article:
(pg 134) - "Following the logic that Mother Nature knows best Shimek (1997, 2000) proposes that a temperature in that range [82-87 degrees Fahrenheit] is best for captive reefs. Our experience in a closed aquarium has demonstrated that the temperature in a closed aquarium should not be maintained near the natural thermal tolerances of corals; on the contrary, it should be maintained significantly lower. The reason for this is due to more than one effect... Our recommendation to maintain reef aquariums at cooler temperatures assumes that the goal is to maintain a diverse population of corals, other reef life and fish in a stable environment that promotes their long-term health with minimal risk of disease or accidental suffocation...High temperature in combination with longer day lengths and salinity changes trigger spawning in the natural environment and in aquariums... coral, anemone, tridacnid clam, [etc] which commonly occurs in the warmest months can be a major problem for closed system aquariums. The release of gametes into the water rapidly consumes oxygen, poisons the tank, clogs the filters, or causes the protein skimmer foam to collapse... [this] is not something that can can be safely managed in a typical closed system aquarium... [however] maintaining a constant, lower temperature in aquariums cannot be considered the definitive means of preventing mass spawning."
(pg 135)
"The principle difference regarding temperature between the natural environment and the aquarium has to do with oxygen availability... the increase in water temperature causes a much more significant issue, the increase in metabolism, and consequently respiration, of the life in the aquarium. The increase in respiration also rises sharply as the thermal tolerance of an animal is approached. This increase in metabolism associated with increase in temperature happens in the natural environment as well, but there it is not as critical as in aquariums because of the ratio of water volume to mass of life."
(pg 136)
"Research on coral bleaching has repeatedly shown that when temperatures exceed the natural temperature extremes by as little as 1 or 2 degrees Celsius, bleaching and subsequent death in corals can occur... Fernando Nosratpour, assistant Aquarium curator at the Birch Aquarium at Scripps in San Diego, reports that the temperature in his Indo-Pacific reef tank ranges from 77 to 83 degrees but is only at 83 for one week in the summer. However, if the temperature rises to 84/85 degrees for ten days or more then signs of bleaching began to appear in the corals."
(pg 137)
"In our experience, the incidence of rapid tissue necrosis (RTN) and other bacterial diseases that affect corals also increases with increasing temperature. Recent scientific research on coral disease supports our aquarium observations... Vibrio coralliilyticus, becomes virulent at just 3 degrees above normal water temperatures and causes complete tissue loss in Pocillopora damicornis. Ben-Haim and Rosenberg (2002) showed that when corals were inoculated with the bacterium at 68 and 77 degrees, no disease appeared after 20 days, but 100% of the tested fragments showed disease and died at 80.6 and 84.2 degrees after just 16 days... [another case] found that when the temperature reached 82.6 degrees an outbreak of Dark Spots Disease occurred. [It was] concluded that conditions within the aquarium might have contributed to this outbreak since the daily temperature fluctuated more than 4.5 degrees and may have created a more stressful situation."
(pg 139) "The bottom line is that an aquarium environment is not the same as the ocean environment. Light fields, light intensity, water chemistry, volume, and water motion in aquariums are all significantly different from those in the ocean."
The book goes on in other sections to talk about other reasons why mid-high 70s is the ideal, but I think I've cited enough. Point is that they provide far more compelling evidence to support their claims than the Shimek article as they are actually talking about experiences within reef aquariums and not just looking at what occurs in the ocean.
I didn't notice at first, but it actually references the Shimek article:
(pg 134) - "Following the logic that Mother Nature knows best Shimek (1997, 2000) proposes that a temperature in that range [82-87 degrees Fahrenheit] is best for captive reefs. Our experience in a closed aquarium has demonstrated that the temperature in a closed aquarium should not be maintained near the natural thermal tolerances of corals; on the contrary, it should be maintained significantly lower. The reason for this is due to more than one effect... Our recommendation to maintain reef aquariums at cooler temperatures assumes that the goal is to maintain a diverse population of corals, other reef life and fish in a stable environment that promotes their long-term health with minimal risk of disease or accidental suffocation...High temperature in combination with longer day lengths and salinity changes trigger spawning in the natural environment and in aquariums... coral, anemone, tridacnid clam, [etc] which commonly occurs in the warmest months can be a major problem for closed system aquariums. The release of gametes into the water rapidly consumes oxygen, poisons the tank, clogs the filters, or causes the protein skimmer foam to collapse... [this] is not something that can can be safely managed in a typical closed system aquarium... [however] maintaining a constant, lower temperature in aquariums cannot be considered the definitive means of preventing mass spawning."
(pg 135)
"The principle difference regarding temperature between the natural environment and the aquarium has to do with oxygen availability... the increase in water temperature causes a much more significant issue, the increase in metabolism, and consequently respiration, of the life in the aquarium. The increase in respiration also rises sharply as the thermal tolerance of an animal is approached. This increase in metabolism associated with increase in temperature happens in the natural environment as well, but there it is not as critical as in aquariums because of the ratio of water volume to mass of life."
(pg 136)
"Research on coral bleaching has repeatedly shown that when temperatures exceed the natural temperature extremes by as little as 1 or 2 degrees Celsius, bleaching and subsequent death in corals can occur... Fernando Nosratpour, assistant Aquarium curator at the Birch Aquarium at Scripps in San Diego, reports that the temperature in his Indo-Pacific reef tank ranges from 77 to 83 degrees but is only at 83 for one week in the summer. However, if the temperature rises to 84/85 degrees for ten days or more then signs of bleaching began to appear in the corals."
(pg 137)
"In our experience, the incidence of rapid tissue necrosis (RTN) and other bacterial diseases that affect corals also increases with increasing temperature. Recent scientific research on coral disease supports our aquarium observations... Vibrio coralliilyticus, becomes virulent at just 3 degrees above normal water temperatures and causes complete tissue loss in Pocillopora damicornis. Ben-Haim and Rosenberg (2002) showed that when corals were inoculated with the bacterium at 68 and 77 degrees, no disease appeared after 20 days, but 100% of the tested fragments showed disease and died at 80.6 and 84.2 degrees after just 16 days... [another case] found that when the temperature reached 82.6 degrees an outbreak of Dark Spots Disease occurred. [It was] concluded that conditions within the aquarium might have contributed to this outbreak since the daily temperature fluctuated more than 4.5 degrees and may have created a more stressful situation."
(pg 139) "The bottom line is that an aquarium environment is not the same as the ocean environment. Light fields, light intensity, water chemistry, volume, and water motion in aquariums are all significantly different from those in the ocean."
The book goes on in other sections to talk about other reasons why mid-high 70s is the ideal, but I think I've cited enough. Point is that they provide far more compelling evidence to support their claims than the Shimek article as they are actually talking about experiences within reef aquariums and not just looking at what occurs in the ocean.
Peter Eichler
New member
Sprung is a good aquarist and wrote some good books but he's been wrong many times before and he'll be wrong again. He's a hobbyist just like many of us and he has been known to follow common beliefs and trends just like many of us. When I want a supplement I don't need I'll trust Sprung. Other than that I'll put a little more faith in natural conditions and personal observations. For years I was made deathly affraid of temps breaking the 80 degree mark because of Sprung, and it was complete and total nonsense.
Scientific research or not, and we all know sometimes even that isn't correct, this not true. At least to the extent that if you took a frag of the same coral and placed it in equal systems with the only difference being one was lit by a 20K Radium and one a 10K Ushio often times the coloration will be very different (out of the tank). "Better" is in the eye of the beholder but they can definately be very different.
Nice thread....good info mostly
Chris
greenbean36191
Premium Member
The magnitude of this problem is very exaggerated. Assuming no thermal stress, (which there shouldn't be over this normal range) going from 78-86 increases metabolism by about 20% and reduces oxygen saturation by about 7%. That equates to about a .5 mg/L loss of oxygen and the actual DO levels will still be around 2 and a half times the safe limit. You're way overstocked or have major aeration issues if temperature is having a noticeable affect on your inhabitants. Regardless of what temperature you run, it's just a bandaid.
The spike you get when you near the tolerance shouldn't be an issue because that spike doesn't occur in most species until 88-92, assuming their natural tolerance hasn't been reduced by low or stable temperatures.
The first part of this statement is indisputable. The second part, IMO only reinforces what Peter has been saying since the first post. You have to ask yourself why these corals are bleaching at temperatures they would regularly see on the reefs in nature and have been shown to be around the range of their growth optima in the lab? If it's something inherent about a captive system then why do so many people in the hobby regularly see those temperatures without ill effect? My tank runs at 86 almost every day during the summer, and sometimes up to 88 or even 90 for a few days, yet bleaching isn't a problem. Dr. Brian Helmuth's work has confirmed that if you keep corals at lower or more stable temps they show extreme stress, while other corals from more natural regimes keep metabolizing normally, even under unnaturally high temps.
Last edited:
greenbean36191
Premium Member
This actually wasn't my point at all. Collection for the hobby is a real threat to the reefs, regardless of how it compares to other factors. My point is that many people in the hobby are under the mistaken impression that stopping the collection of wild fish and corals for the hobby will significantly reduce the amount of animals taken from the reef. It's just not true. The collectors still need to make money and most don't have many other economic alternatives besides harvesting from the reef. If they can no longer sell to us they will just sell to the next highest bidder. There is no shortage of demand for corals and fish from other industries.
Trading frags does little to reduce the amount of animals being taken from the reef and stymies the growth of in situ aquaculture that really could provide economic alternatives for the collectors.
Aquarist007
New member
I apologize for not knowing this thread was alreadystarted on this topic --I've tried to research it with no luck.
I for one, am so greatful to the dedicated moderators on this form that with their leadership and the input of many others hobbyists like mysef, for clearing up or explain alot of misconceptions that I have learned along the way.
I'll state a few :
Biggest misconception was that marine fish don't adapt or have a hard time adapting to change.
The "corrected" statement is that they can adapt to change providing it is within the low and high range of real reef conditions.
Another misconception was based around "Ich" I was totally in the dark about its life cycle and the subsequent treatment to use.
Once I understood the life cycle it made more sense to use a quarantine tank and hyposalinate it.
Another misconception was based around the methods and reasons for treating cyano
And finally for now---the misconception that algae was encouraged by light and reducting light would irradicate it.
This is of course false--the number one factor for increasing the growth of algae is nutrients. finding and cutting down the sources of nutrients will go along way for curbing algae rather then reducing the light.
Way to go Peter----this will be an awesome and valuable thread as it takes off
Scott
I for one, am so greatful to the dedicated moderators on this form that with their leadership and the input of many others hobbyists like mysef, for clearing up or explain alot of misconceptions that I have learned along the way.
I'll state a few :
Biggest misconception was that marine fish don't adapt or have a hard time adapting to change.
The "corrected" statement is that they can adapt to change providing it is within the low and high range of real reef conditions.
Another misconception was based around "Ich" I was totally in the dark about its life cycle and the subsequent treatment to use.
Once I understood the life cycle it made more sense to use a quarantine tank and hyposalinate it.
Another misconception was based around the methods and reasons for treating cyano
And finally for now---the misconception that algae was encouraged by light and reducting light would irradicate it.
This is of course false--the number one factor for increasing the growth of algae is nutrients. finding and cutting down the sources of nutrients will go along way for curbing algae rather then reducing the light.
Way to go Peter----this will be an awesome and valuable thread as it takes off
Scott
aninjaatemyshoe
New member
"Sprung is a good aquarist and wrote some good books but he's been wrong many times before and he'll be wrong again. He's a hobbyist just like many of us and he has been known to follow common beliefs and trends just like many of us. When I want a supplement I don't need I'll trust Sprung. Other than that I'll put a little more faith in natural conditions and personal observations. For years I was made deathly affraid of temps breaking the 80 degree mark because of Sprung, and it was complete and total nonsense."
I don't know what you're talking about regarding the unneeded supplements, I've read through his whole book and never once read something recommending adding supplements beyond the typical calcium, alkalinity, and magnesium. He talks about other trace elements, but doesn't say you "need" to add them.
I'm going to try to make my point clear regarding mid to high 70 degree temperature and stability: It is a GOOD thing. I'm not saying, nor does Sprung's book say, that it is prescriptive for maintaining a healthy reef aquarium. It is simple a great way to further ensure the health of our inhabitants. Why in hell would we be recommending that people don't care about the temperature swings or maintaining a tolerable temperature? Sure, people who have been in the hobby for some time and are quite good at all other elements may need not worry so much, but to the new guys this is bad advice. You talk about your experiences as if they apply to everyone. Tell me one story about someone who maintained the temperature as stated above and had corals suffer for it? I have heard plenty of stories that have pointed to thermal stress causing big problems in their tanks.
"The magnitude of this problem is very exaggerated. Assuming no thermal stress, (which there shouldn't be over this normal range) going from 78-86 increases metabolism by about 20% and reduces oxygen saturation by about 7%. That equates to about a .5 mg/L loss of oxygen and the actual DO levels will still be around 2 and a half times the safe limit. You're way overstocked or have major aeration issues if temperature is having a noticeable affect on your inhabitants. Regardless of what temperature you run, it's just a bandaid."
It is true that the oxygen depletion from higher temps will not be a problem for an aquarium in which there is rather good oxygenation to start with. Problem is that I don't think that is as common as you are assuming. During the night, without the aid of photosynthesis, the oxygen levels can already decrease. Then add on top of that the depleted oxygen from higher temps and you're reaching levels that can put too much stress on our livestock. Certainly, many things such as a reverse daylight refugium, a high turn-over rate on a good protein skimmer, and use of a sump will help alleviate these issues. But as I stated before, unfortunately plenty of aquarists are not providing sufficient oxygenation to make up for such depletion. Sure, we should encourage that they make up for that, but why not also encourage that they keep the temps in a range that will not worsen the problem?
"The spike you get when you near the tolerance shouldn't be an issue because that spike doesn't occur in most species until 88-92, assuming their natural tolerance hasn't been reduced by low or stable temperatures."
So what, are you suggesting that we try and impose hormesis on our livestock by varying the temp and putting them in higher temperature water? How should this practically be acheived? It should be done in a way similar to how it occurs in nature (according to the argument you guys are putting forth). Just simply allowing the temp in our tanks to sway back and forth is not replicating how it occurs in nature, sorry I don't buy it.
"The first part of this statement is indisputable. The second part, IMO only reinforces what Peter has been saying since the first post. You have to ask yourself why these corals are bleaching at temperatures they would regularly see on the reefs in nature and have been shown to be around the range of their growth optima in the lab? If it's something inherent about a captive system then why do so many people in the hobby regularly see those temperatures without ill effect? My tank runs at 86 almost every day during the summer, and sometimes up to 88 or even 90 for a few days, yet bleaching isn't a problem. Dr. Brian Helmuth's work has confirmed that if you keep corals at lower or more stable temps they show extreme stress, while other corals from more natural regimes keep metabolizing normally, even under unnaturally high temps."
Corals do show adaptability to the ranges in which you place them. Once they adapt to that situation, changing the conditions drastically has an obviously negative affect. You can keep them in higher temperature tanks so long as you willing to accept some of the other issues that come along with that. Among the ones listed above, the ones that stick out are the oxygen depletion and the increase in disease activity. Spawning is potentially another issue, but as stated above you don't absolutely avoid it by maintaining lower temperatures.
In the end, it really comes down to what you are going to recommend we should be doing in regards to temperature in our tanks. Telling people they should not care about temp swings is not helping anything. There is no denying that temp swings causes some stress, and in tanks where there already is a good amount of stress from other factors, this can build up to issues such as disease and coral bleaching. As far as what temperature to strive for, I've seen the evidence supporting mid-high 70s and have not seen anything convincing saying low-mid 80s. The idea that keeping a lower temp makes corals vulnerable to higher temps, while valid, is not an adequate reason. After all, the converse could be said about maintaining higher temps; that they make the corals vulnerable to lower temps. Then there is the point made about optimum growth rates, but this is something that applies to certain specific corals in controlled laboratory situations. This is not a real analog to our aquariums, which are not quite so controlled in other factors and contain corals of many different varieties from many different regions and potentially even different oceans.
I don't know what you're talking about regarding the unneeded supplements, I've read through his whole book and never once read something recommending adding supplements beyond the typical calcium, alkalinity, and magnesium. He talks about other trace elements, but doesn't say you "need" to add them.
I'm going to try to make my point clear regarding mid to high 70 degree temperature and stability: It is a GOOD thing. I'm not saying, nor does Sprung's book say, that it is prescriptive for maintaining a healthy reef aquarium. It is simple a great way to further ensure the health of our inhabitants. Why in hell would we be recommending that people don't care about the temperature swings or maintaining a tolerable temperature? Sure, people who have been in the hobby for some time and are quite good at all other elements may need not worry so much, but to the new guys this is bad advice. You talk about your experiences as if they apply to everyone. Tell me one story about someone who maintained the temperature as stated above and had corals suffer for it? I have heard plenty of stories that have pointed to thermal stress causing big problems in their tanks.
"The magnitude of this problem is very exaggerated. Assuming no thermal stress, (which there shouldn't be over this normal range) going from 78-86 increases metabolism by about 20% and reduces oxygen saturation by about 7%. That equates to about a .5 mg/L loss of oxygen and the actual DO levels will still be around 2 and a half times the safe limit. You're way overstocked or have major aeration issues if temperature is having a noticeable affect on your inhabitants. Regardless of what temperature you run, it's just a bandaid."
It is true that the oxygen depletion from higher temps will not be a problem for an aquarium in which there is rather good oxygenation to start with. Problem is that I don't think that is as common as you are assuming. During the night, without the aid of photosynthesis, the oxygen levels can already decrease. Then add on top of that the depleted oxygen from higher temps and you're reaching levels that can put too much stress on our livestock. Certainly, many things such as a reverse daylight refugium, a high turn-over rate on a good protein skimmer, and use of a sump will help alleviate these issues. But as I stated before, unfortunately plenty of aquarists are not providing sufficient oxygenation to make up for such depletion. Sure, we should encourage that they make up for that, but why not also encourage that they keep the temps in a range that will not worsen the problem?
"The spike you get when you near the tolerance shouldn't be an issue because that spike doesn't occur in most species until 88-92, assuming their natural tolerance hasn't been reduced by low or stable temperatures."
So what, are you suggesting that we try and impose hormesis on our livestock by varying the temp and putting them in higher temperature water? How should this practically be acheived? It should be done in a way similar to how it occurs in nature (according to the argument you guys are putting forth). Just simply allowing the temp in our tanks to sway back and forth is not replicating how it occurs in nature, sorry I don't buy it.
"The first part of this statement is indisputable. The second part, IMO only reinforces what Peter has been saying since the first post. You have to ask yourself why these corals are bleaching at temperatures they would regularly see on the reefs in nature and have been shown to be around the range of their growth optima in the lab? If it's something inherent about a captive system then why do so many people in the hobby regularly see those temperatures without ill effect? My tank runs at 86 almost every day during the summer, and sometimes up to 88 or even 90 for a few days, yet bleaching isn't a problem. Dr. Brian Helmuth's work has confirmed that if you keep corals at lower or more stable temps they show extreme stress, while other corals from more natural regimes keep metabolizing normally, even under unnaturally high temps."
Corals do show adaptability to the ranges in which you place them. Once they adapt to that situation, changing the conditions drastically has an obviously negative affect. You can keep them in higher temperature tanks so long as you willing to accept some of the other issues that come along with that. Among the ones listed above, the ones that stick out are the oxygen depletion and the increase in disease activity. Spawning is potentially another issue, but as stated above you don't absolutely avoid it by maintaining lower temperatures.
In the end, it really comes down to what you are going to recommend we should be doing in regards to temperature in our tanks. Telling people they should not care about temp swings is not helping anything. There is no denying that temp swings causes some stress, and in tanks where there already is a good amount of stress from other factors, this can build up to issues such as disease and coral bleaching. As far as what temperature to strive for, I've seen the evidence supporting mid-high 70s and have not seen anything convincing saying low-mid 80s. The idea that keeping a lower temp makes corals vulnerable to higher temps, while valid, is not an adequate reason. After all, the converse could be said about maintaining higher temps; that they make the corals vulnerable to lower temps. Then there is the point made about optimum growth rates, but this is something that applies to certain specific corals in controlled laboratory situations. This is not a real analog to our aquariums, which are not quite so controlled in other factors and contain corals of many different varieties from many different regions and potentially even different oceans.
Peter Eichler
New member
We've really gone overboard with this part of the list and you still seem to insist on saying we're recommending something that we're not.
1.) Julian Sprung is one of those authors that has perpetuated the need to keep temperatures below 80 degrees and incredibly stable. It's an absolute fact that there are many people that have have spectacular aquariums that run over 80 degrees and have fluctuations on warm days and when lights are on throughout the day with no apparent negatives. The unneeded supplement comment is in reference to most of the supplements his company offers. I'd be interested to see what Julian has to say on this topic now
2.) If your oxygen levels are low at 77 degrees they will still be low at 87 degrees. Sure, you could create some slippery slope where oxygen levels are barely sufficient in a tank at a lower temperature and they could become slightly dangerous if the temperature raises, but the chance of that happening is very small. Also, with the event of enexpensive and efficient pumps and skimmers being widely in the hobby now I don't see many people having low oxygen levels in their system.
3.) Greenbean nor I are advocating someone strive for wild temperature fluctuations. Simply put, if your temperatures are going up a few degrees slowly through the course of a day when your metal halide lights go on it's nothing to worry about. Not only that, it's quite natural and very similar to what happens on a reef.
4.) If the fact that temperatures in the 80's are completely natural and that temperature swings occur multiple times a day on a natural reef isn't convincing to you then we're just going to have to agree to disagree. You should also consider the many very successful reef aquariums maintaining temps above 80 and having temp swings as not convincing.
