Dosing Nitrate to reduce Phosphate

[tmz]

With respect to air water interface and gas exchange, the gravity flow to the sump goes across bioballs or whatever to agitate water. I also see it as economy in power consumption, instead of using an additional pump required by the skimmer.
Patrick
Could be a fine alternative if you don't mind the nitrate production and if the surface area provided is large enough to match the surface area of the bubbles. I think it would need to be quite large. I'd also consider how much free oxygen is actually depleted by ammonia oxidizing bacteria that live on those surfaces and bind it to NO2 and NO3 While the nitrate will bump ORP and return the oxygen when it's redcued to N via anerobic activity ,the process may just result in higher nitrate holding some portion of the oxygen. Have you tried it ?

 

[herring_fish]

Perhaps I just missed it but what do you mean by CO2 scrubbers. Do you feed the scrubbers with CO2?

 

[tmz]

It's a container filled with soda lime through which air passes on it's way to the skimmer intake. The media commonly used in diving rebreathers and medical anesthesia applications adsorbs CO2 from the air before it goes to the tank via gas exchange in the skimmer.

 

[2_zoa]

The bubbles in a skimmer offer exponentially more surface area than the surface of a typcial aquarium.
I think any surface film present is permeable to gas exchange in the agitated water in a skimmer. If it wasn't fresh air to skimmer intakes and CO2 scrubbers wouldn't have the effect they do on raising pH via CO2 reduction. Mine export lot's of organics and have lots of evident surface film since I dose organic carbon ;adding a CO2 scrubber nonetheless raises pH by .15.Many also hook up airlines to the outdoors to skimmer intakes with similar effect in reducing CO2 via gas exchange.

So, I'm by far no expert and this is one of my many weaknesses. However, I was recently learned, that CO2 scrubbers don't do anything to help PH through gas exchange. By keeping the CO2 out, your helping to stop carbonic acid from forming. That acid is what drives the ph down, Right?

I'm trying to make sure I understand the process clearly cause I can read your post two ways. Maybe carbonic acid has nothing to do with it?

One: Not knowing anything, thinking that CO2 and O2 cause and effect the other. Meaning, O2 will drive CO2 out of the water column.

Two: The assumption is made that the reader knows how the dissolved gasses work and how the tank benefits from a more pure O2 bubble. Perhap the tank has a low O2 saturation, not necessarily effecting CO2 levels.

 

[Subsea]

Nitrate factory

Nitrate factory

With respect to air water interface and gas exchange, the gravity flow to the sump goes across bioballs or whatever to agitate water. I also see it as economy in power consumption, instead of using an additional pump required by the skimmer.
Patrick
Could be a fine alternative if you don't mind the nitrate production and if the surface area provided is large enough to match the surface area of the bubbles. I think it would need to be quite large. I'd also consider how much free oxygen is actually depleted by ammonia oxidizing bacteria that live on those surfaces and bind it to NO2 and NO3 While the nitrate will bump ORP and return the oxygen when it's redcued to N via anerobic activity ,the process may just result in higher nitrate holding some portion of the oxygen. Have you tried it ?

Tom,
I spent 4 months testing bioballs and 6 other media used in reef aquariums. I will link the test criteria. I disagree with the assumption of bioballs being a nitrate factory.
Patrick

1. Coarse substrate has processed 144 ml of ammonia. NH4 at 4ppm and NO4 at 100ppm
2. Oolite sand has processed 106 ml of ammonia. NH4 at 8ppm and NO4 at 150ppm
3. Bio balls have processed 263 ml of ammonia. NH4 at 8ppm and NO4 at 10ppm
4. Sponge Bob has processed 276 ml of ammonia. NH4 at less than .5 ppm and NO4 at 5 ppm
5. Home made ceramic rock is removed from study due to substandard showing.
6. Live Rock has processed 252 ml of ammonia. NH4 at .5 ppm and NO4 at 20 ppm
7. Rock rubble has processed 445 ml of ammonia. NH4 at .5 ppm and NO4 at <5 ppm
8. Control tank has processed 80 ml of ammonia. NH4 at 4 ppm and NO4 at 150 ppm.

http://www.nano-reef.com/topic/337332-nitrate-factory/

Randy had previously discussed some of the limitations of the testing. Nevertheless, bioballs outperformed live rock in processing nitrogen, introduced as ammonia.
Patrick

 

[tmz]

I never said nitrate factory, Ammonia oxidation creates nitrite then nitrate. Ammonia oxidizing bacteria colonize surfaces in oxygenated water in applications of bioballs or other media.

 

[Subsea]

I never said nitrate factory, Ammonia oxidation creates nitrite then nitrate. Ammonia oxidizing bacteria colonize surfaces in oxygenated water in applications of bioballs or other media.

Tom,
Quite splitting hairs. The point in question is that bioballs processed more nitrate than live rock.
Patrick

 

[tmz]

So, I'm by far no expert and this is one of my many weaknesses. However, I was recently learned, that CO2 scrubbers don't do anything to help PH through gas exchange. By keeping the CO2 out, your helping to stop carbonic acid from forming. That acid is what drives the ph down, Right?

Mostly yes, CO2 hydrolyzes producing H ;some of that goes to from carbonic acid . Not very much actually does the carbonioc acid part in salt water but that doesn't matter the H is acidic; ph is a measure of H whether it's in carbonic acid , bicarbonate or other forms. . It's the CO2 and the H it produces when it hydrolyzes that lowers pH.

I'm trying to make sure I understand the process clearly cause I can read your post two ways. Maybe carbonic acid has nothing to do with it?

One: Not knowing anything, thinking that CO2 and O2 cause and effect the other. Meaning, O2 will drive CO2 out of the water column.

O2 and CO2 are unrelated ,you can have a tank superstaurated with oxygen and low pH from high CO2. At very high levels of injection one may drive off the other as would the injection of another other gas in a solution sealed from the air ;just a matter of space for soluble gases in solution . However, the gases in solution will equilibriate with the surrounding air in an unsealed container like an aqurium over a relatively short period of time via gas exchange which occurs at the surface of the bubble or the surface of the tank or other water air interface areas .

Two: The assumption is made that the reader knows how the dissolved gasses work and how the tank benefits from a more pure O2 bubble. Perhap the tank has a low O2 saturation, not necessarily effecting CO2 levels.

It's not an assumption; just a brief direct answer to a question about what a CO2 scrubber is. without taking the thread too far off topic.

Tanks are not usually undersaturated with oxygen; they are often overstaruated with CO2 from high levels in the room air and or the biological activity in the tank. A CO2 scrubber does not add oxygen to the air ; it does remove some CO2 from the room air passing through it and when the scrubbed air air meets the water at the air water interface CO2 equilibriates via gas exchange with the effect of reducing the amount of CO2 in the water. The earth's air /athmosphere is mostly nitrogen at 78% anyway with oxygen around 21% and CO2 a scant 390ppm or about 4 tenths of one percent. In homes CO2 levels are often higher than athmospheric CO2 levels.

This thread of mine on CO2 scrubbers provides additional information for those intersted in more detail:

http://www.reefcentral.com/forums/showthread.php?t=1889552&highlight=co2+scrubber

 

[tmz]

This section from Randy H. Farley's article on seawater explains saturation levels and athospheric gas levels in seawater :

Dissolved Atmospheric Gases
<hr align="left" size="1px" width="75%" color="#006699"><table align="right" width="43%" cellpadding="2" cellspacing="2"> <tbody><tr> <td> <table align="right" bgcolor="#E8FAFF" border="2" width="300"> <tbody><tr bgcolor="#006699"> <td colspan="2">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Table 4. Atmospheric gases in seawater at 25°C when in equilibrium with air.[/SIZE][/FONT]​

</td> </tr> <tr bgcolor="#FFFFFF"> <td width="143"> [FONT=Georgia, Times New Roman, Times, serif][SIZE=-1]Gas[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1]Concentration[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Carbon dioxide (as HCO₃^- and CO₃^--)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 100 ppm of CO₂[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Nitrogen (N₂)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 10.7 ppm[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Oxygen (O₂)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 6.6 ppm[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Argon (Ar)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 0.40 ppm[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Neon (Ne)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 0.13 ppb[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Helium (He)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 0.0066 ppb[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Krypton (Kr)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 0.185 ppb[/SIZE][/FONT]​

</td> </tr> <tr> <td width="143">[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] Xenon (Xe)[/SIZE][/FONT]</td> <td width="139">

[FONT=Georgia, Times New Roman, Times, serif][SIZE=-1] 0.038 ppb[/SIZE][/FONT]​

</td> </tr> </tbody></table> </td> </tr> </tbody></table>Any gas present in the atmosphere will be present in seawater. Many of these are unimportant to reef aquarists, but two are of critical importance: oxygen and carbon dioxide. Aside from carbon dioxide, all of the gases have lower solubility in seawater as the temperature and salinity are raised. Table 4 shows the concentration of the most common gases in seawater at 25°C.
Oxygen is generally most highly concentrated near the ocean's surface. In the top 50 meters or so, oxygen's concentration is controlled largely by exchange with the atmosphere, and is usually close to equilibrium with the air. Between 50 and 100 meters, the O[SIZE=-1]2[/SIZE] level often rises due to photosynthesis. Below about 100 meters in the open ocean the oxygen level drops steadily for the next 1000 meters or so due to biological processes that consume it. It then sometimes rises again in the deeper oceans as oxygen there is replenished by sinking cold ocean water that is rich in oxygen. The importance of dissolved oxygen in seawater and reef aquaria has been discussed in a series of previous articles:
The Need to Breathe in Reef Tanks: Is it a Given Right?
http://www.reefkeeping.com/issues/2005-06/eb/index.php
The Need to Breathe, Part 2: Experimental Tanks
http://www.reefkeeping.com/issues/2005-07/eb/index.php
The Need to Breathe, Part 3: Real Tanks and Real Importance
http://reefkeeping.com/issues/2005-08/eb/index.php
Carbon dioxide is a special case. It hydrates on contact with water to form carbonic acid, which can then ionize (break apart) to from hydrogen ions, bicarbonate and carbonate, as shown below.
CO₂ + H₂O ßà H₂CO₃ ßà H⁺ + HCO₃^- ßà 2H⁺ + CO₃^--
<table align="left" width="43%" cellpadding="2" cellspacing="2"> <tbody><tr> <td height="201"> <table align="left" bgcolor="#E8FAFF" border="2" width="293"> <tbody><tr bgcolor="#006699"> <td colspan="2">

[SIZE=-1]Table 5. Fate of carbon dioxide in the ocean after 1000 years.[/SIZE]​

</td> </tr> <tr bgcolor="#FFFFFF"> <td width="157"> [SIZE=-1]Form/Location[/SIZE]
</td> <td width="125">

[SIZE=-1]Percentage[/SIZE]​

</td> </tr> <tr> <td width="157">[SIZE=-1] CO₂ in the atmosphere[/SIZE]</td> <td width="125">

[SIZE=-1]1.4%[/SIZE]​

</td> </tr> <tr> <td width="157">[SIZE=-1] CO₂/H₂CO₃ in the ocean[/SIZE]</td> <td width="125">

[SIZE=-1]0.5%[/SIZE]​

</td> </tr> <tr> <td width="157">[SIZE=-1] HCO₃^- in the ocean[/SIZE]</td> <td width="125">

[SIZE=-1]79.9%[/SIZE]​

</td> </tr> <tr> <td width="157">[SIZE=-1] CO₃^-- in the ocean[/SIZE]</td> <td width="125">

[SIZE=-1]9.6%[/SIZE]​

</td> </tr> <tr> <td width="157">[SIZE=-1] Organics on land[/SIZE]</td> <td width="125">

[SIZE=-1]4.9%[/SIZE]​

</td> </tr> <tr> <td width="157">[SIZE=-1] Organics in the ocean[/SIZE]</td> <td width="125">

[SIZE=-1]3.7%[/SIZE]​

</td> </tr> </tbody></table> </td> </tr> </tbody></table>For this reason, carbon dioxide is much more soluble in seawater than is any other atmospheric gas. It is more soluble than all the other gases combined, in fact, with a total solubility of about 100 ppm of carbon dioxide. An interesting question to ask is, "What happens to carbon dioxide that is mixed into the ocean?" After 1000 years, it is thought that it ends up in the forms shown in Table 5.
Additional discussion of carbonate and bicarbonate in seawater is provided in subsequent sections of this article.
Many other gases are dissolved in seawater, but it is beyond the scope of this article to describe all of them. Many have biological significance, including hydrogen sulfide (H[SIZE=-1]2[/SIZE]S), methane (CH[SIZE=-1]4[/SIZE]) and other organic gases, carbon monoxide (CO), hydrogen (H[SIZE=-1]2[/SIZE]) and nitrous oxide (N[SIZE=-1]2[/SIZE]O).


The complete article can be found here:


http://reefkeeping.com/issues/2005-11/rhf/index.php#8

 

[tmz]

Tom,
Quite splitting hairs. The point in question is that bioballs processed more nitrate than live rock.
Patrick

Stop attempting to marginalize or label my input as hair splitting or just dismiss it. It's insulting and untrue. I've not labeled any of yours.

The point of the discussion is whether a wet dry or trickle filter with highly oxygenated water and surface area produces nitrate vs a skimmer. An attempt to divert discussion to a broad discussion of optimal nitrification location confuses the question but doesn't change it.

It's not about the bioballs; it's about whether a highly oxygenated aqueous environment with surface area for colonization by ammonia oxidizing bacteria , whether using live rock, rubble, ceramic beads. porous stones or bioballs, etc. in a high oxygen flow environment produces nitrate.It does;it's a fundamental stage of the nitrogen cycle.

There is a clear difference between a skimmer and methods employing lots of surface area in oxic water .

Skimmers offer no surface area for bacteria to colonize,so no nitrification occurs in them as no nitrifying bacteria colonize there ; it does occur where oxygen and ammonia and surface are available. If you don't see that difference or understand it then you don't but it's pretty clear to me.

 

[herring_fish]

I’m reading this thread because I got rid of too much nitrate and I want to know the best way to fix it. I don't want to do it again in a different way either.

If I learn a little extra stuff along the way then that’s OK with me.

 

[Subsea]

The point in question was that bioballs processed nitrate. Your point was declaring you did not say "nitrate factory". I did not see that relevant to the conversation.

When you compare/contrast the mechanical extraction of bacteria using surface tension, I get it. It is a completely different nutrient management process. Apples and oranges.

They are not mutually exclusive. I choose not to use it as I prefer the biological processes of nutrient recycling.

You and I look at things from differrent viewpoints. For example, when you say exudates of algae, it is a bad thing to be removed from the display tank. I and Julian Sprung see it as "marine snow" a food for coral.
Patrick

PS. It is getting late and I am tired. If I offended you, I apologize.

 

[2_zoa]

This thread of mine on CO2 scrubbers provides additional information for those intersted in more detail:

http://www.reefcentral.com/forums/showthread.php?t=1889552&highlight=co2+scrubber

Thank you very much for taking the time. (Both posts) I'm gonna go read now. Haha

:beer:

 

[tmz]

Thank you very much for taking the time. (Both posts) I'm gonna go read now. Haha

:beer:

You are welcome. Enjoy.

 

[tmz]

I spent 4 months testing bioballs and 6 other media used in reef aquariums.

I see you've added your measures of various media. I assume you measured ammoina as total amonia,ie NH3 and NH4. Is that right ? What is NO4?

 

[tmz]

I’m reading this thread because I got rid of too much nitrate and I want to know the best way to fix it. I don't want to do it again in a different way either.

If I learn a little extra stuff along the way then that’s OK with me.

If you are convinced you have a nitrogen deficiency and want more nitrate adding sodium nitrate is probably the easiest most direct way to boost it. For the turf scrubber you may want to think about iron too.

 

[herring_fish]

Yep. Thanks
I do find that iron helps and I have used it, off and on, for years. The problem is that I often forget that I need it. These reminders help.

I like these side journeys of detailed explanation. If I am not that interested in that particular flavor of the day or if I have already read that study, I can always skip it. "¦but if it is something that I hadn't thought about, why not learn a little.

 

[Subsea]

I spent 4 months testing bioballs and 6 other media used in reef aquariums.

I see you've added your measures of various media. I assume you measured ammoina as total amonia,ie NH3 and NH4. Is that right ? What is NO4?

My bad. NO4 should have been NO3. Nitrate.

Total ammonia was read as NH3/NH4. I used inexpensive API test kit to determine ammonia feed rate for each test study tank. It was my intention to maximize ammonia feed by maintaining concentrations between 1-8 ppm. The second criteria was nitrate concentration. When NO3 reached 150 ppm I discontinued ammonia feed. When nitrate dropped to 50 ppm, I reestablished ammonia feed. Not exactly reef conditions. The point was to focus on bacteria and in particular, nitrogen bacteria processors.

A part of the quality assurance and quality control for the experiment involved Ward Lab to validate my testing results. I can send a link if you wish to scrutinize their protocol.
Patrick

 

[Subsea]

Ward Lab

Ward Lab

Because I find testing boring and I lack patience, I use an outside lab for my quest in affordable knowledge..
Patrick

http://wardlab.com/FeeSchedule/WardLabs_FeeSchedule_Web.pdf#page=10

W-1A Sub-Surface Irrigation .................................................................. $61.00
Sodium Nitrate Total Hardness (Lime) Iron
Calcium Carbonate Total Alkalinity Iron Bacteria
Magnesium Bicarbonate Boron Manganese
Potassium Sulfate Sodium Adsorption Ratio (SAR) Acid Titration Curve
Chloride Electrical Conductivity Adj. SAR pHc
pH Est. Total Dissolved Solids
W-2 Nitrate Sulfate.................................................................................. $8.50
W-3 Nitrate............................................................................................... $5.50

I test my ground water periodically using the above protocol. Ward Lab knows my unusual needs as a mariculture facility. I used their protocol to determine the chemical composition of Gracilaria Parvispora.
Patrick

 

[herring_fish]

Good stuff Patrick. I was writing this before the last post. I am now talking about home test kits.

I was asking Herring fish what he dosed and to what level of NOe, since I'm interested in his anecdotal observation.

This made me remember a question that had plagued me throughout my reefing life. That is, how do I get better readings for 0 Nitrate? It’s not truly zero. What is it?

I am sure this is an easy one to answer but the alternate concentration test suggestion that are given in the typical instructions for common test kits don’t help at indicating anything useful when you get to lower levels of N. Again, this is probably an easy one to answer.

In the old days, lots of people would be very happy to see a bright yellow reading of zero. I read a lot, then design and built a custom super ATS and right way I was blessed with zero N and P. Then I notice that I saw signs of what I call over scrubbing but you can get levels that are too low in a balanced or unbalanced way by using many other methods as well.

Fast forward to today. Carbon dosers, skimmers, GFO users, Lanthumum users and so many other people have no trouble successfully staying in the low range. If you look around this sight, you can find others that are trying to find a proper level for both N and P. Some people report of SPS coloring up when an exact amount of this or that is in the water column on a constant basis. Xenia lovers look for the right levels to get controlled growth but not week like growth. There are a few people that are zeroing in of not-zero.

…but how do I see with better resolution in the very low range?