Let me preface this by saying that I'm starting a refugium right now. Also, I studied computer science and physics in school and I can't balance a chemical equation; I'm not sharp there.
I've been reading about coral reefs (at my mortal level of intelligence, mind you) and have encountered some contradicting information. Primarily, the role of algae in the reef ecosystem. As we know, algae abundance is bad -- it can smother corals, look ugly, and clog up equipment. One way some combat algae is through refugiums on the premise that they "out compete" the algae in the display tank. A seemingly unnatural (though our tanks are inherently unnatural) part of the ecosystem based on my reading. However, from my understanding of reefs, this could actually be a detriment in some circumstances. According to Coral Reefs in the Microbial Seas (Forrest Rohwer, Merry Youle), DDAM (DOC, Death, Algae, and Microbes) is responsible for a large amount of reef bleaching events. The theory states that the overgrowth of algae can potentially release excess DOC (dissolved organic carbon) into the water column, thus providing a wealth of nutrients for microbes to consume and grow. If the microbes in the coral encounter these nutrients and grow too quickly, they could potentially consume the local oxygen at such a rate that the coral is asphyxiated. Additionally, some turf algae has been shown to carry specific pathogens that can cause white-band disease in corals through the means of physical contact. Sources: Coral Reefs in the Microbial Seas 104-115; additional sources used by the text are cited there as well.
Based on this understanding, could popular refugium algae such as Chaetomorpha, provide the conditions necessary to harm coral health?
The text continues to describe the importance of herbivores (and the entire upper food chain) of a reef. Without the herbivores, the algae can grow excessively, consuming the nutrients and elements (hope I'm not butchering this) needed for growth (phosphorous, iron, nitrogen) disproportionately quickly. However, the algae can continue to photosynthesize without growing -- by releasing excess DOC into the water. Taking this point quite a bit out of context, could it be reasonable to assume that you can have too large of a Fuge which can have these effects; too much chaeto starving the corals not only for nutrients but also CO2 AND producing excess DOCs? Can this reinforce the importance of managing algal blooms (especially GHA) on the grounds that they can not only starve the corals, but produce microbe-feeding DOCs and potentially harbor bacteria and phages (this might be stretching it) that can harm corals? Sources: Coral Reefs in the Microbial Seas 104-110; additional sources used by the text are cited there as well.
What about in a mature reef? It seems lots of mature reefs can handle excess feeding / nutrients better than younger reefs. Many attribute this to bacterial diversity and population (probably right); but what about surface area? If the algae can't grow anywhere because everything is covered by coral colonies, it cannot take hold, and thus those excess nutrients fuel coral growth instead of DOC-releasing algae? OR, the excess nutrients prevent algae from releasing DOC because it is always able to create biomass from photosynthesis VS extra DOC because of the availability of nitrogen and phosphorous; so even if it did take hold in a mature or high nutrient reef, it wouldn't have as devastating of an impact?
Lastly, could the distance from refugium to coral have an impact? Can DOCs released from Chaetomorpha or others breakdown quickly so they can't make it to a coral / could proximity of turf algae to coral be a factor in coral health we haven't thought of as much from a reef hobbyist perspective?
If you're still with me and don't hate me for butchering that, I'd love to hear your thoughts! I really want to learn more about how reefs work and the biochemistry behind it. Maybe it's time I tried to learn some basic chemistry.
I've been reading about coral reefs (at my mortal level of intelligence, mind you) and have encountered some contradicting information. Primarily, the role of algae in the reef ecosystem. As we know, algae abundance is bad -- it can smother corals, look ugly, and clog up equipment. One way some combat algae is through refugiums on the premise that they "out compete" the algae in the display tank. A seemingly unnatural (though our tanks are inherently unnatural) part of the ecosystem based on my reading. However, from my understanding of reefs, this could actually be a detriment in some circumstances. According to Coral Reefs in the Microbial Seas (Forrest Rohwer, Merry Youle), DDAM (DOC, Death, Algae, and Microbes) is responsible for a large amount of reef bleaching events. The theory states that the overgrowth of algae can potentially release excess DOC (dissolved organic carbon) into the water column, thus providing a wealth of nutrients for microbes to consume and grow. If the microbes in the coral encounter these nutrients and grow too quickly, they could potentially consume the local oxygen at such a rate that the coral is asphyxiated. Additionally, some turf algae has been shown to carry specific pathogens that can cause white-band disease in corals through the means of physical contact. Sources: Coral Reefs in the Microbial Seas 104-115; additional sources used by the text are cited there as well.
Based on this understanding, could popular refugium algae such as Chaetomorpha, provide the conditions necessary to harm coral health?
The text continues to describe the importance of herbivores (and the entire upper food chain) of a reef. Without the herbivores, the algae can grow excessively, consuming the nutrients and elements (hope I'm not butchering this) needed for growth (phosphorous, iron, nitrogen) disproportionately quickly. However, the algae can continue to photosynthesize without growing -- by releasing excess DOC into the water. Taking this point quite a bit out of context, could it be reasonable to assume that you can have too large of a Fuge which can have these effects; too much chaeto starving the corals not only for nutrients but also CO2 AND producing excess DOCs? Can this reinforce the importance of managing algal blooms (especially GHA) on the grounds that they can not only starve the corals, but produce microbe-feeding DOCs and potentially harbor bacteria and phages (this might be stretching it) that can harm corals? Sources: Coral Reefs in the Microbial Seas 104-110; additional sources used by the text are cited there as well.
What about in a mature reef? It seems lots of mature reefs can handle excess feeding / nutrients better than younger reefs. Many attribute this to bacterial diversity and population (probably right); but what about surface area? If the algae can't grow anywhere because everything is covered by coral colonies, it cannot take hold, and thus those excess nutrients fuel coral growth instead of DOC-releasing algae? OR, the excess nutrients prevent algae from releasing DOC because it is always able to create biomass from photosynthesis VS extra DOC because of the availability of nitrogen and phosphorous; so even if it did take hold in a mature or high nutrient reef, it wouldn't have as devastating of an impact?
Lastly, could the distance from refugium to coral have an impact? Can DOCs released from Chaetomorpha or others breakdown quickly so they can't make it to a coral / could proximity of turf algae to coral be a factor in coral health we haven't thought of as much from a reef hobbyist perspective?
If you're still with me and don't hate me for butchering that, I'd love to hear your thoughts! I really want to learn more about how reefs work and the biochemistry behind it. Maybe it's time I tried to learn some basic chemistry.