Your post reminded me of something Cjharles Delbeek said a long time ago:
"When I see the colors of some of these low nutrient tanks, I can't help but be reminded of bleached coral reefs. It should therefore not come as a surprise that feeding corals in such systems becomes a very important component in these systems. Though reefs are often catagorized as nutrient "deserts" the influx of nutrients in the form of particulates and plankton is quite high when the total volume of water passing over a reef is taken into consideration.
Our crystal-clear aquaria do not come close to the nutrient loads that swirl around natural reefs. And so when we create low-nutrient water conditions, we still have to deal with the rest of a much more complex puzzle. Much like those who run their aquarium water temperature close to the thermal maximums of corals walk a narrow tight rope, I can't help but think that low-nutrient aquariums may be headed down a similar path." Charles Delbeck, Coral Nov/Dec 2010, pg 127
Southampton ran a system for over decade and one result was a minimum PO4 level of .03 mg/l to minimize the risk of disrupting coral photobiology. Best way to increase your PO4 is just feed fish more and stop using GFO. Beside phosphorus fish poop also provides nitrogen and carbon. Here's some stuff you may find informative, I'm also including stuff on microbiomes as they are essential for healthy coral reefs and corals
"Coral Reefs in the Microbial Seas"
Changing Seas - Mysterious Microbes
Nitrogen cycling in hte coral holobiont
BActeria and Sponges
Maintenance of Coral Reef Health (refferences at the end)
Optical Feedback Loop in Colorful Coral Bleaching
Richard Ross What's up with phosphate"
An experimental mesocosm for long-term studies of reef corals - Volume 92 Issue 4
www.cambridge.org
An Experimental Mesocosm for Longterm Studies of Reef Corals
Phosphate Deficiency:
Nutrient enrichment can increase the susceptibility of reef corals to bleaching:
Increased dissolved inorganic nitrogen (DIN) concentrations in sea water have been linked to a reduction of the temperature threshold at which corals bleach, however, the mechanism underlying this change is not known. This phenomenon is now explained in terms of increased phosphatase activities...
www.nature.com
Ultrastructural Biomarkers in Symbiotic Algae Reflect the Availability of Dissolved Inorganic Nutrients and Particulate Food to the Reef Coral Holobiont:
Reef building corals associated with symbiotic algae (zooxanthellae) can access environmental nutrients from different sources, most significantly via the up...
www.frontiersin.org
Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates
Enrichment of reef environments with dissolved inorganic nutrients is considered a major threat to the survival of corals living in symbiosis with din…
www.sciencedirect.com
Effects of phosphate on growth and skeletal density in the scleractinian coral Acropora muricata: A controlled experimental approach
Phosphate contamination can negatively affect corals, modifying growth rates, skeletal density, reproduction, mortality, and zooxanthellae. We determi…
www.sciencedirect.com
High phosphate uptake requirements of the scleractinian coral Stylophora pistillata
SUMMARYSeveral untested aspects of the regulation of inorganic nutrient uptake were examined using nutrient depletion experiments with the symbiotic coral Stylophora pistillata. The total inhibition of phosphate uptake in artificial seawater lacking sodium indicates the involvement of a...
jeb.biologists.org
Phosphorus metabolism of reef organisms with algal symbionts
2657円まるいち 博多辛子明太子(無着色) 「博多の華」 (ギフト用) 180g Z6572海産物イクラ,タラコ,魚卵 Qoo10] 「博 まるいち 博多辛子明太子(無着色) | therichross.com
therichross.com
Sponge symbionts and the marine P cycle
Marine sponges are ubiquitous colonizers of shallow, clear-water environments in the oceans (1, 2). Sponges have emerged as significant mediators of biogeochemical fluxes in coastal zones by virtue of respiring organic matter and facilitating both the consumption and release of nutrients (3, 4)...
www.pnas.org
Phosphorus sequestration in the form of polyphosphate by microbial symbionts in marine sponges
Coral reefs are highly productive ecosystems that raise a conundrum called “Darwin’s paradox”: How can high production flourish in low-nutrient conditions? We show here that in three abundant Caribbean sponges, the granules that have been commonly observed in sponge tissue for decades are...
www.pnas.org
