Nitrate consumption - how fast does it happen?

[kilnakorr]

My nitrates seems to drop at a decent rate, the last few months.
I'm running very little gfo to keep phosphates in check (0.06) but even with a few more fish, increased feedings, dosing a bit of KNO3 and running water pass my roller filter it stills drops.
As there any rule of thumb on how much nitrate is consumed in a reef tank?

 

[The_Paradox]

My nitrates seems to drop at a decent rate, the last few months.
I'm running very little gfo to keep phosphates in check (0.06) but even with a few more fish, increased feedings, dosing a bit of KNO3 and running water pass my roller filter it stills drops.
As there any rule of thumb on how much nitrate is consumed in a reef tank?

Mainly depends on algae and corals. My coral heavy tank consumes ~2.5ppm per day.

 

[Tripod1404]

I have seen rates as high as ~24 PPM equivalent per day if not more. I had a pump set to add 1 PPM nitrate per hour every day, and it would barely be detectable. So the actual max rate of consumption may have been higher if I dosed more.

This was when I had large chuck of cheato in the sump that would fully fill the fuge chamber (and it was so dense that it almost acted like a mesh filter).

I greatly reduced my cheato now since controlling trace elements like potassium and iron got annoying, and I would get coraline algae die offs due to it

 

[The_Paradox]

I have seen rates as high as ~24 PPM equivalent per day if not more. I had a pump set to add 1 PPM nitrate per hour every day, and it would barely be detectable. So the actual max rate of consumption may have been higher if I dosed more.

This was when I had large chuck of cheato in the sump that would fully fill the fuge chamber (and it was so dense that it almost acted like a mesh filter).

I greatly reduced my cheato now since controlling trace elements like potassium and iron got annoying, and I would get coraline algae die offs due to it

Love it! Live dangerous. Just tested and this is actually high for me and I run 10-11 dKH.

 

[kilnakorr]

Mainly depends on algae and corals. My coral heavy tank consumes ~2.5ppm per day.

Except for coralline and the slowly forming dust on the glas, I have zero algea.

I have seen rates as high as ~24 PPM equivalent per day if not more. I had a pump set to add 1 PPM nitrate per hour every day, and it would barely be detectable. So the actual max rate of consumption may have been higher if I dosed more.

This was when I had large chuck of cheato in the sump that would fully fill the fuge chamber (and it was so dense that it almost acted like a mesh filter).

I greatly reduced my cheato now since controlling trace elements like potassium and iron got annoying, and I would get coraline algae die offs due to it

I think I might set nitrate on the doser.
Nice to hear a heavy stocked tank, can consume so much nitrate.

Gotta add some nitrate, then do a test and check how much the uptake really is in my tank, on a daily basis.

 

[Tripod1404]

Except for coralline and the slowly forming dust on the glas, I have zero algea.

I think I might set nitrate on the doser.
Nice to hear a heavy stocked tank, can consume so much nitrate.

Gotta add some nitrate, then do a test and check how much the uptake really is in my tank, on a daily basis.

Make sure you start slow and measure daily for some time. Most organisms can store nitrate, so the initial consumption can appear higher than it actually is, simply because it is being pulled into storage by cells. Once their storage is full, consumption will drop and you will be able to see actual rate of consumption.

In my opinion it is better to nitrate dosing level below your actual rate of consumption. Like if you measure the rate of consumption at 15 PPM, I would dose 10 PPM or less.

 

[The_Paradox]

In my opinion it is better to nitrate dosing level below your actual rate of consumption. Like if you measure the rate of consumption at 15 PPM, I would dose 10 PPM or less.

I try to dose ~5% over and then manually skip a day as needed. Adjustments up usually needed every 2-3 months. If I don’t stay on it or leave it off too long is when I start to see dinoflagellates.

 

[Dburr1014]

I was 0 nitrate for a long time. As long as you feed and have phosphates.
I started dosing ammonium chloride.

Thread 'DIY Ammonia dosing for low nitrate systems' https://www.reef2reef.com/threads/diy-ammonia-dosing-for-low-nitrate-systems.987087/

 

[Randy Holmes-Farley]

Make sure you start slow and measure daily for some time. Most organisms can store nitrate, so the initial consumption can appear higher than it actually is, simply because it is being pulled into storage by cells. Once their storage is full, consumption will drop and you will be able to see actual rate of consumption.

In my opinion it is better to nitrate dosing level below your actual rate of consumption. Like if you measure the rate of consumption at 15 PPM, I would dose 10 PPM or less.

What is the evidence for N storage?

 

[Randy Holmes-Farley]

IMO, one should not try to match a rate of consumption, but rather adjust dosing to maintain your target range whatever it may be.

 

[The_Paradox]

I was 0 nitrate for a long time. As long as you feed and have phosphates.

About that.

This was a few weeks ago when I went to readjust.

 

[Tripod1404]

What is the evidence for N storage?

Intracellular nitrate storage by diatoms can be an important nitrogen pool in freshwater and marine ecosystems - Communications Earth & Environment

The accumulation and storage of nitrate by diatoms can contribute up to 1% of total pelagic nitrate and as much as 95% of total benthic nitrate, which indicates a potentially important contribution of diatoms to benthic nitrogen cycling, according to a global analysis

www.nature.com

Diatom abundance and total intracellular nitrate contents in water columns, sediments, microbial mats, and epilithic biofilms were highly significantly correlated. In contrast, diatom community composition had only a marginal influence on total intracellular nitrate contents. Nitrate concentrations inside diatom cells exceeded ambient nitrate concentrations ∼100–4000-fold. The collective intracellular nitrate pool of the diatom community accounted for <1% of total nitrate in pelagic habitats and 65–95% in benthic habitats.

Concentration and transport of nitrate by the mat-forming sulphur bacterium Thioploca - Nature

MARINE species of Thioploca occur over 3,000 km along the continental shelf off Southern Peru and North and Central Chile1–4. These filamentous bacteria live in bundles surrounded by a common sheath and form thick mats on the sea floor under the oxygen-minimum zone in the upwelling region, at...

www.nature.com

We report here that Thioploca cells are able to concentrate nitrate to up to 500 mM in a liquid vacuole that occupies >80% of the cell volume.

https://journals.asm.org/doi/abs/10.1128/aem.62.3.954-958.1996

These filamentous, sulfur-oxidizing bacteria accumulate nitrate intracellularly at concentrations of 130 to 160 mM, 3,000- to 4,000-fold higher than ambient levels.

And this a review covering multiple species and ecosystems.

Frontiers | Nitrate Storage and Dissimilatory Nitrate Reduction by Eukaryotic Microbes

The microbial nitrogen cycle is one of the most complex and environmentally important element cycles on Earth and has long been thought to be mediated exclus...

www.frontiersin.org

Many benthic and pelagic diatoms accumulate nitrate intracellularly in concentrations up to a few 100 mM, but concentrations can be as low as zero to a few mM.

Foraminifers may store nitrate at concentrations >15,000 times the environmental nitrate concentrations , probably in vacuoles , and the measured intracellular nitrate pool varies among nitrate-storing foraminifers from ca. 0.1 mM to >375 mM.

Gromiids belong to the Rhizaria, and their intracellular nitrate concentrations can also reach >100 mM, which exceeds the ambient nitrate concentration by several orders of magnitude .

To date, only a single strain of A. terreus (fungi) isolated from a marine sediment has been shown to store nitrate intracellularly and use it for dissimilatory nitrate reduction mainly to ammonium. The intracellular nitrate concentration in this strain reached up to 0.4 mM.

The chlorophyte Dunaliella tertiolecta stored nitrate at 2.7–4.9 mM in one study , but had intracellular nitrate concentrations below the detection limit in another study . Similarly, the dinoflagellate Amphidinium carterae stored 0–1.8 mM nitrate , while the dinoflagellate Prorocentrum minimum did not store nitrate . Among the haptophytes, Isochrysis galbana stored 0.3–13.9 mM nitrate and Pavlova lutheri only stored 0.1–0.2 mM nitrate . Clearly, more investigations focusing on intracellular nitrate storage in these lineages are needed.

I am more familiar with nitrate storage in land plants, which can be a massive pool. Some plants can grow without any visible inhibition for months living of the vacuolar nitrate stores.

 

[kilnakorr]

IMO, one should not try to match a rate of consumption, but rather adjust dosing to maintain your target range whatever it may be.

Isn't that the same thing. Dosing to maintain a target, would be matching the uptake?

Anyway, I added nitrate earlier and tested a couple of hours later and got 5.5.
Will test same time the next few days to see if the uptake is more or less linear.

 

[Randy Holmes-Farley]

Isn't that the same thing. Dosing to maintain a target, would be matching the uptake?

Anyway, I added nitrate earlier and tested a couple of hours later and got 5.5.
Will test same time the next few days to see if the uptake is more or less linear.

Yes, but it does not require any correct information about the uptake rate before you start. Thus, any changes in demand caused by any changes in, say, available nitrate concentration, or the possibility of some organisms storing N become unimportant to know and/or understand in detail.

 

[Randy Holmes-Farley]

Intracellular nitrate storage by diatoms can be an important nitrogen pool in freshwater and marine ecosystems - Communications Earth & Environment

The accumulation and storage of nitrate by diatoms can contribute up to 1% of total pelagic nitrate and as much as 95% of total benthic nitrate, which indicates a potentially important contribution of diatoms to benthic nitrogen cycling, according to a global analysis

www.nature.com

Concentration and transport of nitrate by the mat-forming sulphur bacterium Thioploca - Nature

MARINE species of Thioploca occur over 3,000 km along the continental shelf off Southern Peru and North and Central Chile1–4. These filamentous bacteria live in bundles surrounded by a common sheath and form thick mats on the sea floor under the oxygen-minimum zone in the upwelling region, at...

www.nature.com

https://journals.asm.org/doi/abs/10.1128/aem.62.3.954-958.1996

And this a review covering multiple species and ecosystems.

Frontiers | Nitrate Storage and Dissimilatory Nitrate Reduction by Eukaryotic Microbes

The microbial nitrogen cycle is one of the most complex and environmentally important element cycles on Earth and has long been thought to be mediated exclus...

www.frontiersin.org

I am more familiar with nitrate storage in land plants, which can be a massive pool. Some plants can grow without any visible inhibition for months living of the vacuolar nitrate stores.

OK, thanks. I'm not sure how important this is in a reef tank, since I'm not sure how large of a user of nitrate those organisms typically are, but I see they can directly store N in various ways and I appreciate the references.

FWIW, I've not heard of anyone overshooting their nitrate target in a problematic way.

 

[kilnakorr]

Just for an update, all though I'll keep testing a couple more days.

Sunday at 19.00: 5.5 ppm
Monday at 19.00: 4.5 ppm
Tuesday at 19.00: 3.5 ppm

so far it seems my nitrate is dropping exactly 1.0 ppm a day.

 

[library 112]

I have seen rates as high as ~24 PPM equivalent per day if not more. I had a pump set to add 1 PPM nitrate per hour every day, and it would barely be detectable. So the actual max rate of consumption may have been higher if I dosed more.

This was when I had large chuck of cheato in the sump that would fully fill the fuge chamber (and it was so dense that it almost acted like a mesh filter).

I greatly reduced my cheato now since controlling trace elements like potassium and iron got annoying, and I would get coraline algae die offs due to it

When you had your dousing pump did you add it straight , mixed with water, sump etc. just curious. I am fighting low nitrate right now and trying to balance my phosphate as well. I’m dosing 4ml of nyos nitrate plus a day. Mixed with rodi water in my dosing pump. …

 

[Tripod1404]

When you had your dousing pump did you add it straight , mixed with water, sump etc. just curious. I am fighting low nitrate right now and trying to balance my phosphate as well. I’m dosing 4ml of nyos nitrate plus a day. Mixed with rodi water in my dosing pump. …

I added it straight to the sump after the refugium chamber. But my pump was on a timer, so I would divide my daily consumption to 24 and add that amount per hour. If you are only adding 4ml that should not really matter that much.