Relationship between NO3, PO4, Alk, and PAR

[arking_mark]

There was a very interesting thread on this:

Light, Alkalinity, Nutrients.

I'd like to hear your thoughts of the relationships of these 3 parameters. For example, I've seen recommendations to adjust nutrient levels upwards if running high alkalinity, which seems to defy Liebig's Law of the Minimum which states the rate of photosynthesis is regulated by the least...

www.reef2reef.com

My takeaway was:

Post in thread 'Light, Alkalinity, Nutrients.' https://www.reef2reef.com/threads/light-alkalinity-nutrients.319223/post-9454985

If these are the general principles:
1. Low P (phosphorous limited) higher PAR leads to bleaching
2. High N (Nitrogen rich) lower Alk leads to reduced growth and browning.

Then...

ULNS should have lower PAR and lower Alk.

High N / Low P systems should have lower PAR and higher Alk.

Low N / High P systems should have higher PAR and lower Alk.

High N / High P systems should have higher PAR and Higher Alk.

Are these principles accepted in the reefing community?

If so, the question is what are the recommended values for SPS, LPS, Softies depending on the style of tank your running?

We know old school reefers were successful with ULNS which many tried to emulate for years. Could it be they were more successful because lighting wasn't as tunable as it is today and they targeted NSW Alk and achieved ULNS with lower PAR and lower Alk?

 

[Miami Reef]

High N / Low P systems should have lower PAR and higher Alk.

Low P should have lower alk IMO.

 

[blaxsun]

I really don't know how many reefers run ULNS anymore, to be honest. If anything, I think there's more of a trend to run nutrients in the 5-10ppm/0.05-0.10 nitrate/phosphate range. I'm not running excessive PAR (even my SPS is well below 200), and while I'm not seeing phenomenal coral growth everything is stable, happy and healthy for the most part.

In answer to your question, yes - there may have been a method to the madness with the 'old school' way of doing things.

 

[Lavey29]

I really don't know how many reefers run ULNS anymore, to be honest. If anything, I think there's more of a trend to run nutrients in the 5-10ppm/0.05-0.10 nitrate/phosphate range. I'm not running excessive PAR (even my SPS is well below 200), and while I'm not seeing phenomenal coral growth everything is stable, happy and healthy for the most part.

In answer to your question, yes - there may have been a method to the madness with the 'old school' way of doing things.

Wow under 200 with SPS? Not acros right maybe stylos or birdsnest or monti?

 

[blaxsun]

Wow under 200 with SPS? Not acros right maybe stylos or birdsnest or monti?

Chip's acro, actually. The top of it is maybe 150-175 PAR. I've got 3 monticaps in ~125-150 PAR right now - all are doing fine. I've got some other smaller SPS in the 115-125 PAR range as well.