Nitrate increase oxidative stress

[BeanAnimal]

Maybe poor choice of word but you're totally missing my point by worrying about semantics. The study concludes that elevated nitrate only becomes destructive when corals face severe phosphorus starvation under heat, an asset mismatch that a steady input of fish food prevents in a home tank.

I am not missing your point (we’ll get to that in a moment). I was making sure the idea of a “balanced” water column ratio of N and P was not being asserted or promoted. It is a common misconception in this hobby worth correcting. I opted to overlook the other more technical problems with the post. But since you insist that I missed your point, let’s examine it.

You responded by telling me what the study “concludes,” but it does not say nitrate is harmful only under heat stress and severe phosphate starvation. Nitrate enrichment occurred before heat was applied and also showed adverse effects. Heat made the response worse.

“Fish food makes nitrate and phosphate rise and fall proportionally.” By what measure? They are consumed and exported through different processes, at different rates. Feeding does not guarantee that either remains in the water column, let alone that their readings rise and fall proportionally. A well fed tank can still be phosphate limited.

Mature live rock may very well have helped your tanks, and the organisms it brings can be beneficial. But “more biodiversity” is too abstract and is often presented with no real definition.. More of what, and how did you determine it helped? Why is more better? The absence of nuisance algae does not answer either question. We don't have a definition of biodiversity or better here. Just something to think about when promoting the idea the more "biodiversity" is better.

And lastly: You indicated
“Dosing ammonium or urea risks toxic free ammonia.”
As with any dosing, proper care is needed. Randy addresses this in his ammonia dosing article. Dosing too much of anything can pose acute risks.

 

[ereeef]

I am not missing your point (we’ll get to that in a moment). I was making sure the idea of a “balanced” water column ratio of N and P was not being asserted or promoted. It is a common misconception in this hobby worth correcting. I opted to overlook the other more technical problems with the post. But since you insist that I missed your point, let’s examine it.

You responded by telling me what the study “concludes,” but it does not say nitrate is harmful only under heat stress and severe phosphate starvation. Nitrate enrichment occurred before heat was applied and also showed adverse effects. Heat made the response worse.

“Fish food makes nitrate and phosphate rise and fall proportionally.” By what measure? They are consumed and exported through different processes, at different rates. Feeding does not guarantee that either remains in the water column, let alone that their readings rise and fall proportionally. A well fed tank can still be phosphate limited.

Mature live rock may very well have helped your tanks, and the organisms it brings can be beneficial. But “more biodiversity” is too abstract and is often presented with no real definition.. More of what, and how did you determine it helped? Why is more better? The absence of nuisance algae does not answer either question. We don't have a definition of biodiversity or better here. Just something to think about when promoting the idea the more "biodiversity" is better.

And lastly: You indicated
“Dosing ammonium or urea risks toxic free ammonia.”
As with any dosing, proper care is needed. Randy addresses this in his ammonia dosing article. Dosing too much of anything can pose acute risks.

I completely agree that N and P export rates differ and that raw dosing requires proper care. My point is simply that a mature, high-input home system handles nutrient availability very differently than a controlled lab environment where elements are strictly isolated under thermal stress.

To be clear im not asserting or promoting any mathematical ratio in the water column; im simply pointing out that having both nutrients available as a joint input prevents the absolute phosphate starvation that the lab environment intentionally forced. the entire study is explicitly centered around heat stress (simulating ocean warming heatwaves). im not swinging temps in my home system

 

[BeanAnimal]

You’ve narrowed your point, but your remarks thus far don’t align with the study.

They did not “intentionally force” phosphate starvation. The tanks had a continuous flow of natural seawater that contained a measured level of phosphorus. They stopped feeding the corals, but there was still a supply of phosphorus. We don’t know if phosphorus was depleted.

Sure, the study is centered on heat stress, but that is irrelevant to the adverse effects reported during nitrate enrichment before heat was applied. Your tank temperature has nothing to do with what the study measured.