Carbon dosing: Giving corals the P they need?

[LadyTang2]

I wont mention which industry member said this but I wanted to see what everyone here and of course @Randy Holmes-Farley has to say about this claim...

That carbon dosing is great for corals specifically because corals have difficulty getting P and after carbon dosing polyps can eat the bacteria which have that P they need. So basically more bacteria grow, then get eaten by coral, giving them the P they needed.

True? Maybe? Likely?

 

[Daddy-o]

I do think the bacteria become part of a reef tank food chain.

 

[Dana Riddle]

A little background:

Coral Nutrition, Part Two: Foods for Corals - Reefs.com

Coral Nutrition, Part Two: Foods for Corals - While once reefkeepers believed lighting and chemical additives were all we needed to sustain corals, coral nutrition is now recognized as vital for a thriving captive reef. Dana Riddle delves into more detail about foods for coral.

www.advancedaquarist.com

 

[LadyTang2]

A little background:

Coral Nutrition, Part Two: Foods for Corals - Reefs.com

Coral Nutrition, Part Two: Foods for Corals - While once reefkeepers believed lighting and chemical additives were all we needed to sustain corals, coral nutrition is now recognized as vital for a thriving captive reef. Dana Riddle delves into more detail about foods for coral.

www.advancedaquarist.com

Great article Dana! Took a while to read but I got most of it, I think. Question about the article....

I took away that fish poop is good and that yes coral can eat bacteria. At the end you write "Organic phosphorus (bound in bacteria tissue) is the preferred phosphate source (as opposed to dissolved reactive phosphate.)"

1. Can I control which phosphate the bacteria are eating, if I dosed this organic phosphate while carbon dosing so the bacteria grew with a source of this usable organic phosphate, would that be better. Or is organic phosphate not available or I cannot do this, I really dont know but I think you see my idea, what do you think?

2. Do you generally agree then that carbon dosing, since it boosts bacteria and your article shows coral eat bacteria, that you can say carbon dosing is good for coral health?

 

[taricha]

2. Do you generally agree then that carbon dosing, since it boosts bacteria and your article shows coral eat bacteria, that you can say carbon dosing is good for coral health?

To answer your question 2, we'd have to know how the populations of bacteria respond to carbon doses.
Different carbon sources grow bacteria differently, and it's not known if the bacteria we grow on our carbon sources is at all related to the bacteria that corals want and try to cultivate to eat. Some people on this forum argue the opposite, that our carbon doses grow harmful bacteria. They point to studies showing correlations between organic carbon levels and bacteria that negatively affect coal health. On the other hand, the hobby is full of carbon dosing, and corals do ok (in spite, or because of??)

Definitive answers will probably have to come through aquabiomics service and their projects probing the actual make-up of aquarium bacteria.

 

[Randy Holmes-Farley Verified Community Expert]

I wont mention which industry member said this but I wanted to see what everyone here and of course @Randy Holmes-Farley has to say about this claim...

That carbon dosing is great for corals specifically because corals have difficulty getting P and after carbon dosing polyps can eat the bacteria which have that P they need. So basically more bacteria grow, then get eaten by coral, giving them the P they needed.

True? Maybe? Likely?

I don't know if it is true, but it is possible. I do know filter feeders grew better when I was carbon dosing.

 

[Randy Holmes-Farley Verified Community Expert]

Great article Dana! Took a while to read but I got most of it, I think. Question about the article....

I took away that fish poop is good and that yes coral can eat bacteria. At the end you write "Organic phosphorus (bound in bacteria tissue) is the preferred phosphate source (as opposed to dissolved reactive phosphate.)"

1. Can I control which phosphate the bacteria are eating, if I dosed this organic phosphate while carbon dosing so the bacteria grew with a source of this usable organic phosphate, would that be better. Or is organic phosphate not available or I cannot do this, I really dont know but I think you see my idea, what do you think?

2. Do you generally agree then that carbon dosing, since it boosts bacteria and your article shows coral eat bacteria, that you can say carbon dosing is good for coral health?

I would not assume that corals can take up dissolve organic phosphate (of which there are many millions of different types) any better than, or as well as inorganic phosphate. When consuming bacteria, they are taking in particulate matter.

 

[Dana Riddle]

Great article Dana! Took a while to read but I got most of it, I think. Question about the article....

I took away that fish poop is good and that yes coral can eat bacteria. At the end you write "Organic phosphorus (bound in bacteria tissue) is the preferred phosphate source (as opposed to dissolved reactive phosphate.)"

1. Can I control which phosphate the bacteria are eating, if I dosed this organic phosphate while carbon dosing so the bacteria grew with a source of this usable organic phosphate, would that be better. Or is organic phosphate not available or I cannot do this, I really dont know but I think you see my idea, what do you think?

2. Do you generally agree then that carbon dosing, since it boosts bacteria and your article shows coral eat bacteria, that you can say carbon dosing is good for coral health?

The reason I stated organic P is preferable over inorganic P is this: The inorganic (or ortho P) can stimulate unwanted algal growths. I had a brief conversation with Jamie Craggs of the Horniman Museum in the UK (where they are breeding and raising corals) about dosing nutrients. At one time, they were adding nitrate (and perhaps) others to the coral tanks. They eventually abandoned this and used a more natural method - they simply added more fish. As for carbon dosing, I personally don't do it as I feel heavy feeding of the tank will supply enough. Of course, this might not work in all tanks (those without live rock, no skimmer, etc.) but the N & P levels in my tank are low and BOD testing shows an oxygen drop of just 0.1 or 0.2 mg/L, indicating a light carbon loading.