"Deepwater" Acros- what do we know from working with them?
First off- an apology for being a bit absent from the forum lately.. We've had some pretty crazy sales and all kinds of good stuff happening at Unique Corals, and it's been "dawn to dusk" lately... And, with my assistant out of town, it's been...well, humbling, too! LOL Anyways, things will hopefully sort themselves out and everyone will receive the awesome corals that they purchased during the sales! Here is my latest blah-blah-blah for you to absorb, digest, rip up, ignore, etc...Enjoy!
*******
After you’ve been in the hobby for a few years- or decades- you find yourself searching for things that are new, different, or otherwise unfamiliar to you. If you’re like me, you always find something to keep things stimulating. It’s not hard in this great hobby, is it? For me, one of the coolest and most interesting groups of corals that are becoming more and more prevalent in the trade and hobby these days are the so-called “deepwater” Acropora species. They are proving to be fascinating, surprisingly hardy, and altogether quite different from the more "traditional" Acropora species that we have come to know (LOL. "traditional..").
I think it’s simply because we are receiving a lot of great “deepwater” species from our suppliers lately that I’m getting really into these corals. And, based on the orders and questions we’re receiving- apparently, so are many of our customers. I’ve touched on these corals a long time ago..time to revisit them again in greater detail (okay, I was gonna say “depth”, but just how cliche’d would that have been, huh?). Hopefully, we can touch on some things that might provide a bit more than the usual “I’ve had this coral and it is really touchy”-type forum posts that we’re accustomed to seeing with these “deepwater” threads. Hence, my absurd title... I'm not suggesting that anything here is the definitive treatise on this group...I only know what I know...But I AM egging you on to do better than just saying that you've had them and they are hard.. Let's get more specific. It will help us all! (This explanation is in anticipation of the inevitable "Fellman you're a self-righteous, wannabe know-it-all and an arrogant a--" type of emails I often receive when I tell us hobby-types to do a better job at something...LOL).
I especially would like to hear from my fellow vendors who work with these corals and might have a lot more to say, or a different experience set wit them than I do, and can add to the body of knowledge.
This is part one of what will probably be a two part look at my new fave coral group…
"I've had a deepwater Acro and they are really touchy." Urgghh.
“Deepwater Acropora” is one of those sort of “reef-hobby-catch-all” terms that we use to describe a number of Acropora species that come from- well- seem to be found predominantly in- er- are found in multiple habitats including- uh, deeper water. Let’s also be honest about one thing…There is no real scientific classification called “deepwater.” Yeah, like “SPS” or “LPS”, it’s one of those artifacts of the “reefkeeping hobby vernacular” that we are so famous for. Nonetheless, it gives us the basis for understanding and discussion, and I say we get a free pass for this one!
Okay, now that I beat the crap out of that point, what are we as hobbyists talking about when we say “deepwater” anyways? Well, for our purposes, let’s say it’s like 45-70 feet. Now, categorically, us reefers tend to simplify things and say that most Acros need bright light and strong water movement, much to the chagrin of coral biologists. On the other hand, most coral biologists have ever kept an Acro in an aquarium, so give yourselves some props here, peeps. So, Moderate to “strong” water movement seems to be a common theme in the so-called “deepwater” Acro husbandry repertoire.
Perhaps the morphology gives us some clues as to their needs?
Well, thats a generalization, but really not far from the truth. I mean, by “strong” in reef terms we mean not strong enough to knock you over, but strong enough to blow the tissue off of some corals. Deepwater Acros seem to be tolerant of moderate to strong indirect water movement. A lot of the areas where they are found have pretty respectable currents, and are often located in rather turbid areas- perhaps a clue to their requirements for captivity? On the other hand, many come from surprisingly calm areas with very little (for the ocean, anyways) water motion. This is a real “slippery slope” for the aquarist, as we are often forced to guess about what types of conditions our corals came from, and have to do some experimentation to see what works. More on that later…
The lighting thing is a bit of a thornier issue, because I have personally found deepwater Acropora to be surprisingly adaptable to a variety of lighting conditions, despite the moniker of “deepwater” attached to them, which implies a shadowy world. Although blue and violet light penetrate deeper on the natural reef than red and green light do, these corals seem to be able to tolerate what we in the reef keeping world would call “moderate to bright” light. They do great under T5 and many acclimate well to halide (like 20000k) and even LED. There seems to be no general “rule”, really, in our experience. Rather, you need to see how the individual specimen does. Acclimation to any new light regimen is, as the great William T, Innes of “Exotic Aquarium Fishes” fame almost a century ago beautifully wrote, “…an act of kindness that is not misspent.”
Careful acclimation to lighting is super important for these corals.
The reality for a lot of “deepwater” species is that they are not truly found in really “deep” water; rather, many are found in areas not associated in our reef keeping mind with Acros (ie; not getting sun baked and slammed with waves on shallow reefs). The morphology (appearance) of “deepwater” species is sort of a giveaway, isn’t it? Visually, we can make very cursory “laymen’s identifications” of these species by examining their skeletal structure. In general, the Acropora that we call “deepwater” tend to exhibit smooth skeletons, and tapering axial corallites. On the other hand, some reefers have argued (and from what positions, I am not sure), that there are simply “smooth skinend” Acros and they are not necessarily deep water growth forms..Oh, boy. Some forms are “coryambose” (ie; they grow outwards from various parts of the main structure to approximately the same length or height), such as A. suharsonoi, while others display more bushy branches, along with the smooth skeletons, and widely spaced, tubular radial and axial corallites that we’ve come to expect from these corals.
Side note: Observations of wild “deepwater” growth forms show that they often grow into large, open “thickets”, which attract, among other species, schools of Apogon Cardinalfishes (J. Adams, per. comm.). An interesting side note for those of us who enjoy the concept of “biotope” aquariums!
These guys would make cool fishes in your "deepwater" Acro reef! Apogon leptacanthus.
Most “deepwater” Acropora species are brownish or tan in color, with subtle highlights. Others have beautiful greens and blues. Then, of course, there are the Acropora carduus, the so-called “Dragon” species, such as the “Red Dragon”, “Pink Dragon”, and “Green Dragon” morphs which exhibit surprisingly strong coloration. Color, of course, is an absolutely horrible way to identify species, but to the reef hobbyist, it’s often the initial “tip off” towards zeroing in on a general coral classification or ID. Scientists, don’t hate on us, ‘cause we’ve done a lot of amateur science and learned just a few things about these cool corals, despite or rampant use of over-generalizations! in fact, the irony is that most of the information available on the life requirements of the so-called “deepwater” species has been accumulated by reef hobbyists…Keep up the good work, guys!
One thing that is rather challenging is identification of so-called “deepwater” species. We often find ourselves staring at a coral and asking ourselves, “Is this Acropora granulosa or A. echinata”…or perhaps a form of Acropora multiacuta…?” You know, the usual stuff that occupies ones day….
Seriously, it can be challenging to identify some of these species. Others, like Acropora fenneri , have a very distinctive “sawblade”-like morphology, and a rather easy to point out in a lineup of otherwise similarly-appearing “deepwater” Acros. The good news, in our experience, anyways, is that the vast majority of these species seem to thrive under similar contains, making that old reef keeping standby of employing the generalization useful in many instances!
Acropora suharsonoi..right? Or multiacuta? Umm..
With quality mariculture operations in Bali and elsewhere “farming” these species, the selection, quality, and general availability has never been better. For the most part, they ship surprisingly well, and we seem to rarely lose a specimen during the importation process. Acclimation for “deepwater” species is straightforward- a slow drip like you’d do for any other coral seems to work just fine.
As discussed previously in our blogs, at Unique Corals, we have developed the habit of “unplugging” maricultured Acros , cutting them off of the mariculture base and gluing them to inert ceramic frag plugs/discs. This seems to aid in shipping, as well as in general health for many of the specimens we work with. Without the potential for die-off of the life forms that the maricultured base “recruited” while in the ocean, and the possibility of pest introduction, they encrust quickly and ship much better for us.
However, for every rule there is an exception, and the “deepwater” species are just that. We have found that they are often best left on the mariculture bases, because they typically do not encrust at the base, or take a very long time to do so. This means that we are extra vigilant in observation, quarantine, and prophylactic pest control measures with these corals. Many of our customers remove them from the plugs upon arrival, and glue them directly to the reef structure in their aquarium without issues.
Categorically, most deepwater species do not fare all that well when exposed to iodine-based dips. I know a number of very successful aquarists that swear by Bayer as a prophylactic coral dip, even for so-called “deepwater” species. I have not tried this personally, however, so I cannot vouch for its safety based on my own experience.
One thing we can say is that these corals seem to withstand imposed propagation (ie; fragging) really well, and grow with remarkable rapidity if they are healthy and well cared for. Thugs is in stark contrast to many reports that suggest that they are super slow growers. Now, we’re not growing them to colony size in our facility, but I can state from experience that they seem to grow quickly from small frag (approx. 1”) to salable-sized frag (about 1.5” or so). Later growth to colony size will tend to be a bit slower than say, an Acropora millepora, etc. They almost always start out as lovely brown frags, later regaining their color as they recover from fragging and begin to grow (assuming your conditions are stable).
Another interesting observation is that we typically will grow out the deepwater frags under metal halide (20k Radium) and moderate to strong gyre flow within our raceways. An interesting observation that we have made is that these guys seem to function as a “canary in a coal mine”, often being among the first corals to react if system parameters conditions should deviate from their favored parameters.
Of course, what kinds of parameters are we talking about? Well, in our experience, nothing too exotic, really. Just good, stable water chemistry parameters, such as acceptable “reef level” alkalinity, calcium, and magnesium levels, and modest levels of phosphate and nitrate. I’d be remiss if I didn’t recommend that you try out a Triton ICP-OES water analysis on your system to really get a read on the parameters in your system. Eliminating guesswork and speculation is a key to success with thee or any coral species. However, with the so-called “deepwater” forms, it’s particularly useful as we build up a collective “best practices” for the husbandry of these corals. Trends, exceptions, and commonalities that may be disclosed by such accurate testing will help us better assess the needs of these corals.
Unfortunately, we are often reduced to guessing about the types of conditions under which many Acropora will thrive, and the so-called “deepwater” gang is absolutely no exception. It’s all over the place, and if you ask six different reefers what works, you’ll receive exactly six different answers. Any statement that I make about their care other than observations based on our own experiences is an absolute overgeneralization and would be quite irresponsible, so take all of the information I provide here as simply observations based on what we have seen. Your results may vary- substantially.
That sucks, huh? Yup. Like so many things in this hobby, much of what we know about this group of corals is based upon observations in our aquariums, and is still subject to much speculation and hypothesis o the part of reefers. As we gain more experience with these corals, our “best practices” can hopefully move out of the realm of “this worked for me” to “this is generally agreed upon to be the optimum way to care for these corals.”
Feeding is one of those generally agreed-upon practices for most Acropora, and the deepwater species seem to benefit greatly from regular feeding. Many of the wild-collected specimens arrive Stateside stressed out from the rigors of collection, transport, and acclimation, and are often starving to boot (among the many reasons why we favor maricultured deepwater specimens over wild-collected ones whenever possible). We use the usual types of foods, zooplankton feeds, as well as items like oyster eggs, etc. The important thing is that these corals seem to require a lot of food- perhaps, even more so than their so-called “shallow water” brethren. This is purely anecdotal, but seems to correlate well with our observations. Friends who have dove among so-called “deepwater” form tell me that the water surrounding many of them is surprisingly “turbid”, often with clouds of visible zooplankton. A definite tip, I would think. Many of these corals seem to show a definite and surprisingly rapid feeding response when food is introduced, so the “need to feed” this group should not be taken lightly, IMHO.
In part two of this topic, we’re gonna look at some species in specific, with some more of my personal observations- and the observations of other “deepwater” geeks, and maybe touch on a few other details! As always, please feel free to add your experiences, pics, observations…
Until next time…
Stay Wet.
Scott Fellman
Unique Corals
First off- an apology for being a bit absent from the forum lately.. We've had some pretty crazy sales and all kinds of good stuff happening at Unique Corals, and it's been "dawn to dusk" lately... And, with my assistant out of town, it's been...well, humbling, too! LOL Anyways, things will hopefully sort themselves out and everyone will receive the awesome corals that they purchased during the sales! Here is my latest blah-blah-blah for you to absorb, digest, rip up, ignore, etc...Enjoy!
*******
After you’ve been in the hobby for a few years- or decades- you find yourself searching for things that are new, different, or otherwise unfamiliar to you. If you’re like me, you always find something to keep things stimulating. It’s not hard in this great hobby, is it? For me, one of the coolest and most interesting groups of corals that are becoming more and more prevalent in the trade and hobby these days are the so-called “deepwater” Acropora species. They are proving to be fascinating, surprisingly hardy, and altogether quite different from the more "traditional" Acropora species that we have come to know (LOL. "traditional..").
I think it’s simply because we are receiving a lot of great “deepwater” species from our suppliers lately that I’m getting really into these corals. And, based on the orders and questions we’re receiving- apparently, so are many of our customers. I’ve touched on these corals a long time ago..time to revisit them again in greater detail (okay, I was gonna say “depth”, but just how cliche’d would that have been, huh?). Hopefully, we can touch on some things that might provide a bit more than the usual “I’ve had this coral and it is really touchy”-type forum posts that we’re accustomed to seeing with these “deepwater” threads. Hence, my absurd title... I'm not suggesting that anything here is the definitive treatise on this group...I only know what I know...But I AM egging you on to do better than just saying that you've had them and they are hard.. Let's get more specific. It will help us all! (This explanation is in anticipation of the inevitable "Fellman you're a self-righteous, wannabe know-it-all and an arrogant a--" type of emails I often receive when I tell us hobby-types to do a better job at something...LOL).
I especially would like to hear from my fellow vendors who work with these corals and might have a lot more to say, or a different experience set wit them than I do, and can add to the body of knowledge.
This is part one of what will probably be a two part look at my new fave coral group…
"I've had a deepwater Acro and they are really touchy." Urgghh.
“Deepwater Acropora” is one of those sort of “reef-hobby-catch-all” terms that we use to describe a number of Acropora species that come from- well- seem to be found predominantly in- er- are found in multiple habitats including- uh, deeper water. Let’s also be honest about one thing…There is no real scientific classification called “deepwater.” Yeah, like “SPS” or “LPS”, it’s one of those artifacts of the “reefkeeping hobby vernacular” that we are so famous for. Nonetheless, it gives us the basis for understanding and discussion, and I say we get a free pass for this one!
Okay, now that I beat the crap out of that point, what are we as hobbyists talking about when we say “deepwater” anyways? Well, for our purposes, let’s say it’s like 45-70 feet. Now, categorically, us reefers tend to simplify things and say that most Acros need bright light and strong water movement, much to the chagrin of coral biologists. On the other hand, most coral biologists have ever kept an Acro in an aquarium, so give yourselves some props here, peeps. So, Moderate to “strong” water movement seems to be a common theme in the so-called “deepwater” Acro husbandry repertoire.
Perhaps the morphology gives us some clues as to their needs?
Well, thats a generalization, but really not far from the truth. I mean, by “strong” in reef terms we mean not strong enough to knock you over, but strong enough to blow the tissue off of some corals. Deepwater Acros seem to be tolerant of moderate to strong indirect water movement. A lot of the areas where they are found have pretty respectable currents, and are often located in rather turbid areas- perhaps a clue to their requirements for captivity? On the other hand, many come from surprisingly calm areas with very little (for the ocean, anyways) water motion. This is a real “slippery slope” for the aquarist, as we are often forced to guess about what types of conditions our corals came from, and have to do some experimentation to see what works. More on that later…
The lighting thing is a bit of a thornier issue, because I have personally found deepwater Acropora to be surprisingly adaptable to a variety of lighting conditions, despite the moniker of “deepwater” attached to them, which implies a shadowy world. Although blue and violet light penetrate deeper on the natural reef than red and green light do, these corals seem to be able to tolerate what we in the reef keeping world would call “moderate to bright” light. They do great under T5 and many acclimate well to halide (like 20000k) and even LED. There seems to be no general “rule”, really, in our experience. Rather, you need to see how the individual specimen does. Acclimation to any new light regimen is, as the great William T, Innes of “Exotic Aquarium Fishes” fame almost a century ago beautifully wrote, “…an act of kindness that is not misspent.”
Careful acclimation to lighting is super important for these corals.
The reality for a lot of “deepwater” species is that they are not truly found in really “deep” water; rather, many are found in areas not associated in our reef keeping mind with Acros (ie; not getting sun baked and slammed with waves on shallow reefs). The morphology (appearance) of “deepwater” species is sort of a giveaway, isn’t it? Visually, we can make very cursory “laymen’s identifications” of these species by examining their skeletal structure. In general, the Acropora that we call “deepwater” tend to exhibit smooth skeletons, and tapering axial corallites. On the other hand, some reefers have argued (and from what positions, I am not sure), that there are simply “smooth skinend” Acros and they are not necessarily deep water growth forms..Oh, boy. Some forms are “coryambose” (ie; they grow outwards from various parts of the main structure to approximately the same length or height), such as A. suharsonoi, while others display more bushy branches, along with the smooth skeletons, and widely spaced, tubular radial and axial corallites that we’ve come to expect from these corals.
Side note: Observations of wild “deepwater” growth forms show that they often grow into large, open “thickets”, which attract, among other species, schools of Apogon Cardinalfishes (J. Adams, per. comm.). An interesting side note for those of us who enjoy the concept of “biotope” aquariums!
These guys would make cool fishes in your "deepwater" Acro reef! Apogon leptacanthus.
Most “deepwater” Acropora species are brownish or tan in color, with subtle highlights. Others have beautiful greens and blues. Then, of course, there are the Acropora carduus, the so-called “Dragon” species, such as the “Red Dragon”, “Pink Dragon”, and “Green Dragon” morphs which exhibit surprisingly strong coloration. Color, of course, is an absolutely horrible way to identify species, but to the reef hobbyist, it’s often the initial “tip off” towards zeroing in on a general coral classification or ID. Scientists, don’t hate on us, ‘cause we’ve done a lot of amateur science and learned just a few things about these cool corals, despite or rampant use of over-generalizations! in fact, the irony is that most of the information available on the life requirements of the so-called “deepwater” species has been accumulated by reef hobbyists…Keep up the good work, guys!
One thing that is rather challenging is identification of so-called “deepwater” species. We often find ourselves staring at a coral and asking ourselves, “Is this Acropora granulosa or A. echinata”…or perhaps a form of Acropora multiacuta…?” You know, the usual stuff that occupies ones day….
Seriously, it can be challenging to identify some of these species. Others, like Acropora fenneri , have a very distinctive “sawblade”-like morphology, and a rather easy to point out in a lineup of otherwise similarly-appearing “deepwater” Acros. The good news, in our experience, anyways, is that the vast majority of these species seem to thrive under similar contains, making that old reef keeping standby of employing the generalization useful in many instances!
Acropora suharsonoi..right? Or multiacuta? Umm..
With quality mariculture operations in Bali and elsewhere “farming” these species, the selection, quality, and general availability has never been better. For the most part, they ship surprisingly well, and we seem to rarely lose a specimen during the importation process. Acclimation for “deepwater” species is straightforward- a slow drip like you’d do for any other coral seems to work just fine.
As discussed previously in our blogs, at Unique Corals, we have developed the habit of “unplugging” maricultured Acros , cutting them off of the mariculture base and gluing them to inert ceramic frag plugs/discs. This seems to aid in shipping, as well as in general health for many of the specimens we work with. Without the potential for die-off of the life forms that the maricultured base “recruited” while in the ocean, and the possibility of pest introduction, they encrust quickly and ship much better for us.
However, for every rule there is an exception, and the “deepwater” species are just that. We have found that they are often best left on the mariculture bases, because they typically do not encrust at the base, or take a very long time to do so. This means that we are extra vigilant in observation, quarantine, and prophylactic pest control measures with these corals. Many of our customers remove them from the plugs upon arrival, and glue them directly to the reef structure in their aquarium without issues.
Categorically, most deepwater species do not fare all that well when exposed to iodine-based dips. I know a number of very successful aquarists that swear by Bayer as a prophylactic coral dip, even for so-called “deepwater” species. I have not tried this personally, however, so I cannot vouch for its safety based on my own experience.
One thing we can say is that these corals seem to withstand imposed propagation (ie; fragging) really well, and grow with remarkable rapidity if they are healthy and well cared for. Thugs is in stark contrast to many reports that suggest that they are super slow growers. Now, we’re not growing them to colony size in our facility, but I can state from experience that they seem to grow quickly from small frag (approx. 1”) to salable-sized frag (about 1.5” or so). Later growth to colony size will tend to be a bit slower than say, an Acropora millepora, etc. They almost always start out as lovely brown frags, later regaining their color as they recover from fragging and begin to grow (assuming your conditions are stable).
Another interesting observation is that we typically will grow out the deepwater frags under metal halide (20k Radium) and moderate to strong gyre flow within our raceways. An interesting observation that we have made is that these guys seem to function as a “canary in a coal mine”, often being among the first corals to react if system parameters conditions should deviate from their favored parameters.
Of course, what kinds of parameters are we talking about? Well, in our experience, nothing too exotic, really. Just good, stable water chemistry parameters, such as acceptable “reef level” alkalinity, calcium, and magnesium levels, and modest levels of phosphate and nitrate. I’d be remiss if I didn’t recommend that you try out a Triton ICP-OES water analysis on your system to really get a read on the parameters in your system. Eliminating guesswork and speculation is a key to success with thee or any coral species. However, with the so-called “deepwater” forms, it’s particularly useful as we build up a collective “best practices” for the husbandry of these corals. Trends, exceptions, and commonalities that may be disclosed by such accurate testing will help us better assess the needs of these corals.
Unfortunately, we are often reduced to guessing about the types of conditions under which many Acropora will thrive, and the so-called “deepwater” gang is absolutely no exception. It’s all over the place, and if you ask six different reefers what works, you’ll receive exactly six different answers. Any statement that I make about their care other than observations based on our own experiences is an absolute overgeneralization and would be quite irresponsible, so take all of the information I provide here as simply observations based on what we have seen. Your results may vary- substantially.
That sucks, huh? Yup. Like so many things in this hobby, much of what we know about this group of corals is based upon observations in our aquariums, and is still subject to much speculation and hypothesis o the part of reefers. As we gain more experience with these corals, our “best practices” can hopefully move out of the realm of “this worked for me” to “this is generally agreed upon to be the optimum way to care for these corals.”
Feeding is one of those generally agreed-upon practices for most Acropora, and the deepwater species seem to benefit greatly from regular feeding. Many of the wild-collected specimens arrive Stateside stressed out from the rigors of collection, transport, and acclimation, and are often starving to boot (among the many reasons why we favor maricultured deepwater specimens over wild-collected ones whenever possible). We use the usual types of foods, zooplankton feeds, as well as items like oyster eggs, etc. The important thing is that these corals seem to require a lot of food- perhaps, even more so than their so-called “shallow water” brethren. This is purely anecdotal, but seems to correlate well with our observations. Friends who have dove among so-called “deepwater” form tell me that the water surrounding many of them is surprisingly “turbid”, often with clouds of visible zooplankton. A definite tip, I would think. Many of these corals seem to show a definite and surprisingly rapid feeding response when food is introduced, so the “need to feed” this group should not be taken lightly, IMHO.
In part two of this topic, we’re gonna look at some species in specific, with some more of my personal observations- and the observations of other “deepwater” geeks, and maybe touch on a few other details! As always, please feel free to add your experiences, pics, observations…
Until next time…
Stay Wet.
Scott Fellman
Unique Corals
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