Crunching Numbers at LFS - Radion, Nitrate, Phosphate

[Dana Riddle]

Purchased some corals at the LFS today, and took the opportunity to evaluate lighting and nutrients.
They use Radion G4s for lighting. PPFD (or PAR, if you will) ranges from 75 to 175 micromole/m2/sec. Photoperiod is 11 hours at this spectral quality:

UV-A 2.8%
Violet 19.6%
Blue 67.8%
Green-Blue 3.8%
Blue-Green 2.6%
Green 0.8%
Yellow-Green 0.8%
Yellow 0.1%
Orange 0.3%
Red 1.4%

There is a period of 2.5 hours in the morning where additional light is on - I was not able to measure this during this trip. Next time. I can calculate DLI for the data I have. I also ran testing on 'bag water' for nitrate and phosphate. I'll post these later if there seems to be an interest. Good thing I enjoy this - with travel time, lab testing, and number crunching, this adds up to an 8 hour day.
The attached photo doesn't do one of the tanks justice, just the best my cell phone can do.

 

[TexasTodd]

Thanks Dana. It would be good to know which program and % the Radions were running.

 

[Dana Riddle]

Thanks Dana. It would be good to know which program and % the Radions were running.

I'll ask them next time - Tuesday, I think.

 

[Dana Riddle]

Hold your horses! That spectral data is incorrect. I'll have to figure out what went wrong in the Excel program - will get it straightened out this morning. My apologies!

Purchased some corals at the LFS today, and took the opportunity to evaluate lighting and nutrients.
They use Radion G4s for lighting. PPFD (or PAR, if you will) ranges from 75 to 175 micromole/m2/sec. Photoperiod is 11 hours at this spectral quality:

UV-A 2.8%
Violet 19.6%
Blue 67.8%
Green-Blue 3.8%
Blue-Green 2.6%
Green 0.8%
Yellow-Green 0.8%
Yellow 0.1%
Orange 0.3%
Red 1.4%

There is a period of 2.5 hours in the morning where additional light is on - I was not able to measure this during this trip. Next time. I can calculate DLI for the data I have. I also ran testing on 'bag water' for nitrate and phosphate. I'll post these later if there seems to be an interest. Good thing I enjoy this - with travel time, lab testing, and number crunching, this adds up to an 8 hour day.
The attached photo doesn't do one of the tanks justice, just the best my cell phone can do.

 

[Dana Riddle]

Correct data.

UV-A 2.8%
Violet 19.6%
Blue 67.8%
Green-Blue 3.8%
Blue-Green 2.6%
Green 0.8%
Yellow-Green 0.8%
Yellow 0.1%
Orange 0.3%
Red 1.4%

 

[Dom]

I would be interested in the NO3 and PO4 results of the bag. I was shocked to recently test a bag from a thriving tank at the LFS had a NO3 reading of 160+.

 

[Dana Riddle]

Here are the nutrient numbers. Conversion factors below if your test kits report results as nitrate and phosphate.
NO3 as N (Average of 4 measurements): 1.65 mg/L (or ppm if you prefer). Multiply by 4.4 to obtain Atomic Weight of Nitrate.
Phosphorus (as P, of course. Average of 4 measurements): 0.055. Multiply by 3.07 to obtain Atomic Weight of Phosphate (PO4.)

 

[hart24601]

Is there any concern that coral in a bag might produce slime or other compounds during stress that skew the readings so the bag water is quite a bit different than the display?

 

[Dana Riddle]

This picture doesn't do this frag tank justice. Numbers are PPFD (PAR) values in various parts of the tank.
Daily Light Integrals: Lowest (at 75 micromole/m2/sec): 2.97
Highest (at a PAR value of 175): 6.93
Measurements taken with an Apogee Instruments MQ-510 quantum meter. Bear in mind these tanks receive 2.5 hours of full spectrum light before the store opens, so these numbers are representative of 11 hours of light weighted toward the blue end of the spectrum.
The Seneye device reports Photosynthetically Active Radiation (PUR) to be 83%.

 

[Dana Riddle]

Is there any concern that coral in a bag might produce slime or other compounds during stress that skew the readings so the bag water is quite a bit different than the display?

No. Those would be an organic form of nitrogen or phosphorus and would require a strong digestion process to convert them to forms measurable with the reagents I used. Good question though.

 

[KrisReef]

No. Those would be an organic form of nitrogen or phosphorus and would require a strong digestion process to convert them to forms measurable with the reagents I used. Good question though.

Would a Hanna meter get confused or is it similar to your tests?

Thanks for doing this!

 

[Dana Riddle]

Would a Hanna meter get confused or is it similar to your tests?

Thanks for doing this!

Hanna uses the same reagents as those I use (Hach) so organic forms of phosphorus or nitrogen would not be reported.

 

[User1]

This picture doesn't do this frag tank justice. Numbers are PPFD (PAR) values in various parts of the tank.
Daily Light Integrals: Lowest (at 75 micromole/m2/sec): 2.97
Highest (at a PAR value of 175): 6.93
Measurements taken with an Apogee Instruments MQ-510 quantum meter. Bear in mind these tanks receive 2.5 hours of full spectrum light before the store opens, so these numbers are representative of 11 hours of light weighted toward the blue end of the spectrum.
The Seneye device reports Photosynthetically Active Radiation (PUR) to be 83%.

First - thanks Mr. Riddle. Time is time which is money or time away from other things you could be doing, right? So a big thanks for taking the time. Sheesh, a lot of time in there, right? Interesting data.

The tank looks like it is mostly soft coral dominate, correct? Those numbers for par/pur or whatever looks about right. In fact, they also look similar to what I'm keeping although my tank is 30" tall.

 

[Dana Riddle]

First - thanks Mr. Riddle. Time is time which is money or time away from other things you could be doing, right? So a big thanks for taking the time. Sheesh, a lot of time in there, right? Interesting data.

The tank looks like it is mostly soft coral dominate, correct? Those numbers for par/pur or whatever looks about right. In fact, they also look similar to what I'm keeping although my tank is 30" tall.

Thanks and yes that made for a long day. It was my intent to place a data-logging quantum meter's sensor in the tank and record light intensity over a 24-hour period. Unfortunately I was unable to do so. Next week perhaps. The drive and visit to the store was over 3 hours but the biggest time consumer was the testing. I ran 10 tests each on phosphorus and nitrate (some on the fish-only tanks which aren't reported here.) That takes time but is nothing compared to cleaning the glassware before and after testing and cleaning up the mess I make. Yes, you are correct - that tank is mostly zoanthids with a few soft and stony corals.

 

[jda]

Dana - it is interesting to me that you posted this blending light, N and P as a trio. I have just some anecdotes from mainly online observations, but also some local friends of which I am more hands on. I don't post about this much since I have nothing figured out, but I do feel that there is a correlation between lighting type, nitrate and phosphate. ...this is might seem like a ramble, so my apologies up front... so...

I run my tanks with metal halide and NSW level building blocks - .005 to .01 P, .1 N, 6.8-7.0 carbonate and 425-435 calcium. This absolutely gives me the best color and growth where I have constant growth even with coralline algae that can completely cover the glass in a month if not scraped. If I raise any of these even 5x, everything slow down and the color gets more muted with less contrast and brightness. This is also possible with T5s - the many, many Euro Zeo Tanks with 10-12x T5s are a great example. I have noticed a lot of LED lit tanks that need to have higher levels of building blocks at .1-.2P and 2-10N or else their corals can suffer with growth, color and burnt spots - the only difference is the light type. I have seen this with corals that I fragged for locals so we can directly compare with my tanks and theirs. I am well aware that N and P are building blocks and not food/energy, so I have struggled to figure out why this happens, but it seems real and in high enough of numbers to give it some thought, IMO. My only real hypothesis is that the P at 10-20x and N at 20-100x higher than seawater is acting as a semi-poison to the corals in the LED tanks and slows something down so that they don't run out of energy or otherwise stress themselves out. Is there any reason to think that the higher levels of N and P are slowing the coral down and helping in a backwards kind of way? Is Emerson Effect this pronounced?

Anyway, just something that I have been observing and have no answers for, so if you intentionally linked the three, then I am curious to see what you come up with...

FWIW - any aragonite could release P into the water in a bag in a few minutes if from a tank with a different concentrion, so I would get a fresh sample to test N and P.

 

[Dana Riddle]

Wonderful observations, exactly the kind that give me pause for thought. I will go back to that store next week and will test the water on-site to confirm. The method I use to test for nitrate is via cadmium reduction and this reports NO3 lower than actual due to chlorides. Is that what you use? Many of the hobby test kits don't use this method. I have a semi-hypothesis but need to collect a lot more data. What metal halide do you use? I've got maybe 25 lamps in my collection that have only 100 hours or so burn time. Hopefully I have the lamp you use and I can collect some data. Really appreciate your comments.

Dana - it is interesting to me that you posted this blending light, N and P as a trio. I have just some anecdotes from mainly online observations, but also some local friends of which I am more hands on. I don't post about this much since I have nothing figured out, but I do feel that there is a correlation between lighting type, nitrate and phosphate. ...this is might seem like a ramble, so my apologies up front... so...

I run my tanks with metal halide and NSW level building blocks - .005 to .01 P, .1 N, 6.8-7.0 carbonate and 425-435 calcium. This absolutely gives me the best color and growth where I have constant growth even with coralline algae that can completely cover the glass in a month if not scraped. If I raise any of these even 5x, everything slow down and the color gets more muted with less contrast and brightness. This is also possible with T5s - the many, many Euro Zeo Tanks with 10-12x T5s are a great example. I have noticed a lot of LED lit tanks that need to have higher levels of building blocks at .1-.2P and 2-10N or else their corals can suffer with growth, color and burnt spots - the only difference is the light type. I have seen this with corals that I fragged for locals so we can directly compare with my tanks and theirs. I am well aware that N and P are building blocks and not food/energy, so I have struggled to figure out why this happens, but it seems real and in high enough of numbers to give it some thought, IMO. My only real hypothesis is that the P at 10-20x and N at 20-100x higher than seawater is acting as a semi-poison to the corals in the LED tanks and slows something down so that they don't run out of energy or otherwise stress themselves out. Is there any reason to think that the higher levels of N and P are slowing the coral down and helping in a backwards kind of way? Is Emerson Effect this pronounced?

Anyway, just something that I have been observing and have no answers for, so if you intentionally linked the three, then I am curious to see what you come up with...

FWIW - any aragonite could release P into the water in a bag in a few minutes if from a tank with a different concentrion, so I would get a fresh sample to test N and P.

 

[jda]

I gotta use IC to find out on Nitrates. I am just "clear" even on a 10x test using a hobby lot.

I use 14k Phoenix or 20k radium on m80. I don't think that it matters...10k to 22.5k reef bulbs all seem to act the same. I imagine that 6.5k would too, but don't see many of these. ...anything 350 to 850nm+.

Edit: here are some of the basis for my supposition, which I guess that I should state:

1). We know that calcification slows as N and P get higher. This is well proven and peer reviewed with many links that Dr. Holmes-Farley has posted and has in his papers
2). We know that dinos can flourish in environments with high, but not too high, of building blocks, so this probably goes to the dinos(zoox) in the corals as well... darkening, greening and browning of corals.
3). We know that N and P are not food and more does not "feed" the coral more. As long as there is enough when tissue building or repair is happening, then excess does nothing. Adding more is giving the corals more of anything to "use." ...so a small surplus of .1 is no different than a larger surplus of 10 for the true purpose of a building block.
4). We know that too much N and P is a poison to every living creature, just at different amounts.
5). Corals evolved to thrive in a very low N and P environment in nature. Assuming that nature is efficient, or on it's way to efficiency, then this is an ideal environment for these things.

...so, with my limited mental capacity, the only thing that I can come up with is that the rising N and P levels that are multitudes higher than seawater, but not too high for death or serious damage, are somehow stunting something inside of the coral to require less energy from LED light source. This could make sense physiologically with corals, but all that I know is what I read from Veron, Dr. Ron, etc. and I am not that smart. I am sure that you can straighten me out on some of this as to where my assumptions and basis is way off.

I suspect visible-only spectrum being the issue and/or people running too much blue and forsaking above 550nm.

I am probably way off, but trend appears very real in our boxes.

Thanks for the response and your time.

 

[LARedstickreefer]

Hmmm, very interesting. So for us blondes, “excessive” N and P will slow things down if we are also blasting our corals with LEDs?

Instead of shooting for 5ppm Nitrate and 0.1ppm Phosphate, we should be shooting for 1/10 of that, or so? Go ULNS and then raise it a tick?

 

[jda]

I would not change anything based on my supposition. There is no science or peer review, just a theory based on a lot of observations. If you just feel like experimenting, then cool, but there are no conclusions.

Yes, having higher N and P will slow down calcification, but at reasonable levels, stuff will still grow... so if your tank is working, then leave it alone, IMO. If you do want to experiment, then let the coralline be your guide. If you have good levels of the big-3, then coralline will just wear you out with growth with NSW level building blocks. Coralline will slow when the N and P raise just a little bit.

I would avoid the term ULNS. What we are talking about is ocean-level N and P... so natural levels with nothing "ultra low" about them. Ultra Low used to be reserved for levels lower than this where people used media, chemicals and organic carbon to get below natural seawater.

I am still a firm believer in the parameters here, which is a good reference for what Natural Sea Water (NSW) is at:
http://reefkeeping.com/issues/2004-05/rhf/index.php

 

[hart24601]

LED needing higher nutrients might be totally true, however like most things in the hobby I wouldn’t take led and high nutrients as 100%. I run leds, high par 300-500 with most in that upper range, undetectable phosphates (0ppb Hanna ultra low) and just a hint of nitrate on salifert so under 1ppm for sure. I don’t have it set up anymore due to health but here was my tank running those. I know JDA wasn’t impressed by it since there were not basketball size colonies but I got sick before could really grow it out. There seem to be a lot more tanks like this one now then 5 years ago when it was running. Just my experience