Charles Delbeek (N:P, Alk… )

[Dan_P]

Thank you for the reply. The reason why I asked is because I got something totally different out of it. Rather than fixating the ratio I saw him looking at what data he had available and correlate it to troubles they encountered at the aquarium. Then reaching out to peers or other curators to assess their data and troubles, if any, and do that assessment. Expanded upon that with research teams and other data. Cause and correlation. At the end he raised the caveats.

Maybe I read more into the reply than I should have. Apologies.

Diversity in our perspectives, that’s all. It makes us human AI’s so interesting

 

[Dan_P]

Not sure if you’re trying to be sarcastic, funny or what?? Maybe appear smarter than everyone, but it’s a fail on every attempt!

Sorry you didn’t get it.

 

[rishma]

I don’t disagree with the positive perspectives shared about the video but I am not onboard with his focus on the ratio. It was clearly a focus of the talk and the data was really interesting but I am not sure the premise is going to help reef keepers. I am no famous aquarist, just a barely above average hobbyist so my opinion is certainly worth less. As Randy will attest, that doesn’t prevent me from disagreeing at my own peril.

This whole ratio thing started years ago with people latching on to the red field ratio and arguing that algae problems were due to nitrate and phosphate being out of balance. It recently came back up with information from Mike Paletta sharing his view that the ideal nitrate to phosphate ratio for a reef tank should be around 100:1 based on observation. I think the whole concept is as likely to lead people astray and produce positive results.

Delbeek is highly respected for good reason. I think the caveats in his talk will not be understood by many and people will now be seeking 50:1.

My opinion is that reefers will find more success seeking commonly accepted nitrate and phosphate ranges.

 

[Randy Holmes-Farley]

I don’t disagree with the positive perspectives shared about the video but I am not onboard with his focus on the ratio. It was clearly a focus of the talk and the data was really interesting but I am not sure the premise is going to help reef keepers.

On that point, i was surprised for example, to have him call out situations where the N/P ratio was way out of his preferred zone, to not explicitly state each time that the individual parameters (such as nitrate over 100 ppm) might well be the cause, rather than showing it as evidence of the ratio being important. He may have said it in some cases, but my impression was that this hypotheses was not being given equal air time.

It's a difficult thing to distinguish without doing intentional experiments, since as he noted multiple times, different corals respond differently. Thus, a tank where nitrate is 100 ppm and phosphate 1 ppm, putting it into a reasonable zone (say, Richard Ross's tank at some points in time) is not proof that a different tank with the same nitrate and lower phosphate (now falling outside the preferred ratio zone) taht shows problems is because the ratio is bad, the corals are different, or other things are different (alk, pH, trace elements, etc).

Further complicating issues is what the endpoint of good vs bad tank health is. is it disease? (he mentioned that a few times). Disease may relate to lots of things, not the least of which is having those coral pathogens to begin with. Is it growth? Color? Strong skeletons? Resistance to bleaching from temp or other issues?

The whole topic is just very complicated to try to draw conclusions be examining one or 10 or 20 tanks.

As an analogy, how readily can one determine the causes of a human disease or growth rates or whatever by examining 1 or 10 or 20 patients?

That all said, it certainly seems reasonable to me that if one parameter is unusually high (say, nitrate at 100 ppm), that it may make the other (say, phosphate at 0.08 ppm) a limiting nutrient when it might not be in a different and less extreme scenario (say, nitrate at 10 ppm and phosphate at 0.08 ppm). Making phosphate a limiting factor in some scenarios and not others at the same absolute level certainly could have consequences of all kinds, and many might be undesirable.

 

[areefer01]

It's a difficult thing to distinguish without doing intentional experiments, since as he noted multiple times, different corals respond differently. Thus, a tank where nitrate is 100 ppm and phosphate 1 ppm, putting it into a reasonable zone (say, Richard Ross's tank at some points in time) is not proof that a different tank with the same nitrate and lower phosphate (now falling outside the preferred ratio zone) taht shows problems is because the ratio is bad, the corals are different, or other things are different (alk, pH, trace elements, etc).

He talked about one being done around the 32 minute marker with someone moving corals to different environments and comparing growth. Seabird to rat and rat to seabird. Something along those lines. You very well could be talking about different or larger experiments though.

 

[Randy Holmes-Farley]

He talked about one being done around the 32 minute marker with someone moving corals to different environments and comparing growth. Seabird to rat and rat to seabird. Something along those lines. You very well could be talking about different or larger experiments though.

I kind of got lost in the rat seabird discussion. lol

In any case, seabirds vs no seabirds doesn’t seem like a controlled experiment as there may be lots of differences. But maybe if I followed it better it would make more convincing sense.

 

[rishma]

I kind of got lost in the rat seabird discussion. lol

In any case, seabirds vs no seabirds doesn’t seem like a controlled experiment as there may be lots of differences. But maybe if I followed it better it would make more convincing sense.

I’m going to bolus dose seagull poop and monitor coral growth. Will report back.

 

[Koty]

You should…

Seabird nutrients are assimilated by corals and enhance coral growth rates - Scientific Reports

Nutrient subsidies across ecotone boundaries can enhance productivity in the recipient ecosystem, especially if the nutrients are transferred from a nutrient rich to an oligotrophic ecosystem. This study demonstrates that seabird nutrients from islands are assimilated by endosymbionts in corals...

www.nature.com

 

[Randy Holmes-Farley]

Miami keeps birds. Maybe his next project should be to put a perch above his tank and note changes in corals from the droppings. lol

@Miami Reef

 

[Miami Reef]

While we’re at it, what’s stopping us from adding cow manure? lol

 

[Miami Reef]

I feel like it’s necessary to add some photos of Cheese. The harness photo was from when he was a baby.

Now he attacks people that aren’t me. You should have seen him when I took him to
CVS the other week. I grabbed him before he took a bite at the guy. The person thought he liked him lol

He’s a very funny bird. He dances when I make car blinker sounds, flies to me on command, and recently learned to spin on cue.

 

[Randy Holmes-Farley]

What a beautiful bird!

 

[Hans-Werner]

Sorry, I don’t have time to watch a 51 minute video and give comments.

Are there particular comments that are of interest?

The interesting part about nutrients is only 45 minutes long.

Edit: Haha, you already noticed, I was too impatient and didn't read to the end.

 

[Hans-Werner]

You should…

Seabird nutrients are assimilated by corals and enhance coral growth rates - Scientific Reports

Nutrient subsidies across ecotone boundaries can enhance productivity in the recipient ecosystem, especially if the nutrients are transferred from a nutrient rich to an oligotrophic ecosystem. This study demonstrates that seabird nutrients from islands are assimilated by endosymbionts in corals...

www.nature.com

Thanks! I also would have searched this because I didn't know this article yet.

The nutrient analysis was conducted with filtered samples. This means they didn't include particulate phosphates. In seabird poop I would expect a lot of particulate phosphates from fish scales and bones, bacteria etc..

To me it was a bit of a mystery why the seabird island would have a so much wider N : P ratio than the site without seabirds. This throws up the question what happened to the phosphates? Whole fish meal has on average 64.5 % (62 - 68 %) protein which at 16 % N in protein (Kjeldahl nitrogen) calculates to 10.32 % N and an average of 2.47 % phosphorus (2.28 - 2.65 %). This calculates to 7.37 mol/kg N and 0.80 mol/kg P and a molar ratio of 9.2. This is much wider than the site without seabirds but narrower than the seabird island.

I think this is the answer, particluate phosphates were excluded in the analysis.