Dosing Nitrate to reduce Phosphate

[Subsea]

I don't think we are disagreeing here, its more splitting hairs. If your tank runs at a stable nitrate value close to 0 with a carbon dosing system, and you added a small amount of nitrate to bring the level up to a couple of ppm, stopping the addition of nitrate won't lead to continuing increases in the value. If, however, Nitrate was added to a tank that already has issues fixing nitrate then the addition of Nitrate is unwarranted and will just accelerate the problem.

I think some folks want a quick fix and see the bullet points of this discussion and just add nitrate no matter what, thinking it will solve a phosphate issue.

I have tried to be careful in delineating the distinction, but it is sometimes misunderstood. If you have a new tank and you don't yet have stability, Nitrate addition is not a good idea. If you are not carbon dosing, adding Nitrate is also not justified. Personally I have always had a hard time keeping Nitrate higher than 1ppm, and I have always been utilizing a form of carbon dosing. I attribute that to an effective system setup and export mechanism. What originally led me to dosing was that when it went undetectable, my corals became pale and stressed. The color of my corals is much richer and they have done much better with a little bit of nitrate in the system.

Personally I have not seen any increase in algae growth with nitrate in the system, and there are many other tanks here that have seen the same thing, however, each tank's dynamic is different. Thanks for the continuing discussion of this topic

Casey,
Outstanding discussion. Two points to bring up on multiple nutrient pathways and complex food webs. On another thread on this advanced forum, a link was posted, using electron microscopes, that showed microalgae consuming bacteria.
With respect to the ratio of nitrogen to phosphate at 30:1 in Gracilaria Parvispora, it is relatively simple to manage phosphate using macro algae export.
Cheers,
Patrick

PS: I also just recently started carbon dosing with vinegar. I consider this another nutrient management tool. Skimmerless for 40 years.

 

[reefmutt]

Hi Patrick, thanks for the input, but why simple?
With algea consuming 30x more n than p according to your comments and this discussion being about reducing p when n is limited, I don't see how using algea in this context would be simple...
Im not trying to be argumentative, just wanting clarification to help me understand..
But this does motivate me to actually remove my macro algea fuge in hopes of liberating a little more n to help my biopellets bring down my p

 

[Subsea]

What is not simple about it? The point in question is to add enough nitrate with enough corresponding macro algae growth to consume the excess phosphate. For most reefers, particularly SPS systems, this rubs them the wrong way. I hear most hobby forums call for zero nitrate readings. If you want to stunt growth, remove nitrate.
Patrick

 

[Subsea]

In my oldest setup with Jaubert Plenum and mud/macro refugium, I had to add phosphate in the form of dipotassium phosphate. It simple is a "Question of Balance"
Patrick

 

[tmz]

I think nitrogen deficiencies are possible but unlikely in a fed system.Adding nitrate , ammino acids ,less mechanical filtration and/ or increased feeding can remedy such situations. All of those will,however, at some point, even very small amounts of aspartic acid or sodium nirate in my case , will anecdotally enhance nuisance algae growth without discernible effect on PO4 levels in the low range ,IME. I do not think there is an optimal general ratio for nitrate to PO4 in all tanks and adding it should be considered experimental. Nitrate is not the only source of N and may be lower on the prefernce list of many organisms visa a vie ammonia for example.
Phosphate deficiencies are also possible . Excess orgnic C is also a concern in some systems. Then you have iron, potassium, etc to think about as well.
The question of nutrient balance in a given aquarium with it's specific biology is complex not simple and should be carefully considered before jumping into it.

Not sure there is a major disagreement but the following does warrant iteration and clarification,IMO:



It is entirely removed when broken down by bacterial action, becoming nitrogen gas.
A lot of the N is taken up by organics( bacteria, algae ,corals etc) via assimilation and recycled in the aquarium.Some NO3 is present in most tanks ;some at persistent elevated levels when the nitrogen inputs vs the export methods (skimming out bacteria, harvesting macro algae, using a denitrator mechanical filtration and cleaning,water changes, etc.)
Some nitrate is removed via anaerobic bacterial activity as the oxygen is used leaving N , some of which forms N2 and bubbless out as N2 gas. Not all of it though as as some N is stored by various organisms and/or incorpartated in their tissues. N from food , absorbed ammonia, nitirte ,nitrate et alia is assimilated and excess is released contiuously by leaving things . So, there is some N moving around most of the time in a fed tank with living things in it.

 

[herring_fish]

Bacteria Competes With Algae

Bacteria Competes With Algae

I am definitely NO EXPERT but….

As I understand it, in a simplified way, bacteria doesn’t do that great a job of reducing P. Algae may work on N more than P but it does bring down P if it is working properly. Bacteria’s ratio appears to be far worse than algae’s. Unfortunately, when N is too low, algae stops doing its work on either. By adding N when it is too low, algae can go back to work exporting both N and P. So ...N should be low but not too low.

Bacteria can, in some cases, lowers N to a level that stunts the growth of algae by lower N in an unbalanced way. Said in still another way, bacteria competes with the algae for the N. Ramping up the bacteria can adversely affect the algae.

My example is that I had an algae scrubber that was working great. Although I was feeding quite heavily, my water parameters were great and in balance. Then I wanted to add vodka to increase the bacteria levels just as food for some filter feeders.

In two weeks, after cleaning the screen, my algae never grew back. It just stopped growing all together. Well my N and P were good so I just waited to see what would happen. Eventually, the P slowly started to rise although the N stayed very low.

As a side note, my coralline algae stopped growing and started to reseed from the rock. This is an observation that has been reported by other vodka users.

When I started adding N, my algae started growing again, P started to drop and all was right with the world.

 

[tmz]

Yes, I think the extra heterotrophic bacteria can out compete some algae for either N or P but algae species vary in terms of needs for N,P or organic C . Lots of folks see macro and turf algae wane with organic carbon dosing; particualry chaetomorpha;rhodophyta not so much.
I'm planning to try a few different types of macro algae to see if one or more is more viable along side organic C dosing.Some algae species do very well in water with very low nutrients on coral reefs for example (nitrate around 0.2ppm and PO5 around 0.005/ not zero though). In your case there apparently wasn't enough N left for the type of algae in use. The N addition( what did you dose btw?) was therefore helpful. Thanks for the report. Some report similar bounces in algae growth with iron additions,btw.

 

[Subsea]

Elegance in Nature

Elegance in Nature

I think nitrogen deficiencies are possible but unlikely in a fed system.Adding nitrate , ammino acids ,less mechanical filtration and/ or increased feeding can remedy such situations. All of those will,however, at some point, even very small amounts of aspartic acid or sodium nirate in my case , will anecdotally enhance nuisance algae growth without discernible effect on PO4 levels in the low range ,IME. I do not think there is an optimal general ratio for nitrate to PO4 in all tanks and adding it should be considered experimental. Nitrate is not the only source of N and may be lower on the prefernce list of many organisms visa a vie ammonia for example.
Phosphate deficiencies are also possible . Excess orgnic C is also a concern in some systems. Then you have iron, potassium, etc to think about as well.
The question of nutrient balance in a given aquarium with it's specific biology is complex not simple and should be carefully considered before jumping into it.

Not sure there is a major disagreement but the following does warrant iteration and clarification,IMO:



It is entirely removed when broken down by bacterial action, becoming nitrogen gas.
A lot of the N is taken up by organics( bacteria, algae ,corals etc) via assimilation and recycled in the aquarium.Some NO3 is present in most tanks ;some at persistent elevated levels when the nitrogen inputs vs the export methods (skimming out bacteria, harvesting macro algae, using a denitrator mechanical filtration and cleaning,water changes, etc.)
Some nitrate is removed via anaerobic bacterial activity as the oxygen is used leaving N , some of which forms N2 and bubbless out as N2 gas. Not all of it though as as some N is stored by various organisms and/or incorpartated in their tissues. N from food , absorbed ammonia, nitirte ,nitrate et alia is assimilated and excess is released contiuously by leaving things . So, there is some N moving around most of the time in a fed tank with living things in it.

Tom,
Of course biology is not simple. I simple believe in Intelligent Design. The science that maintains ecosystems using dynamic equilibrium works. Its a Question of Balance. When systems are set up in harmony with the laws of nature, they work and they work long term.
Patrick

 

[Subsea]

Yes, I think the extra heterotrophic bacteria can out compete some algae for either N or P but algae species vary in terms of needs for N,P or organic C . Lots of folks see macro and turf algae wane with organic carbon dosing; particualry chaetomorpha;rhodophyta not so much.
I'm planning to try a few different types of macro algae to see if one or more is more viable along side organic C dosing.Some algae species do very well in water with very low nutrients on coral reefs for example (nitrate around 0.2ppm and PO5 around 0.005/ not zero though). In your case there apparently wasn't enough N left for the type of algae in use. The N addition( what did you dose btw?) was therefore helpful. Thanks for the report. Some report similar bounces in algae growth with iron additions,btw.

I dose kelp concentrate from Home Depot at $10/QT. It has every major, minor and trace element except phosphate. Phosphate comes in with the air, I think.
Patrick

PS. Iron gets special consideration. I have found a fresh water substrate from Seachem that leaches iron into system. I also periodically measure iron and dose with a cheleted product manufactured by Seachem.

 

[tmz]

Patrick ,thanks. I was asking Herring fish what he dosed and to waht level of NOe,since I'm intersted in his/her anecdotal observation..

BTW, Phosphate comes in with food ; some with substrate and live rock;not the air except with some dust perhaps.

BTW kelp concentrates are not much on nitrogen or phosphate per this link:


http://www.ext.colostate.edu/mg/gardennotes/234.html#kelpL


This is from it:





Liquid Kelp

Usually cold processed, liquid kelp will have higher levels of growth hormones than extracts. Some may also be enzymatically digested, making the growth hormones even more available to the plants.

<table class="bodyTd" align="right" border="1" width="450" cellpadding="3" cellspacing="1"> <tbody><tr> <td colspan="2">

Liquid Kelp​

</td> </tr> <tr> <td width="177">

Typical NPK analysis​

</td> <td width="202">

Negligible​

</td> </tr> <tr> <td>

Release time​

</td> <td>

Immediate – 1 month​

</td> </tr> <tr> <td>

Pros​

</td> <td>

Adds micronutrients ​

</td> </tr> <tr> <td>

Cons​

</td> <td>

Insignificant nitrogen, phosphorus, and potassium​

</td> </tr> <tr> <td>

Application​

</td> <td>

Mix 1 – 2 tablespoons per gallon of water ​

</td> </tr> </tbody></table>​

 

[Subsea]

It was a joke.

It was a joke.

Patrick ,thanks. I was asking Herring fish what he dosed and to waht level of NOe,since I'm intersted in his/her anecdotal observation..

BTW, Phosphate comes in with food ; some with substrate and live rock;not the air except with some dust perhaps.

I should have said, lol, when I said "Phosphate comes in with the air, I think".
Patrick

 

[tmz]

Wern't sure if you were kidding. I thought it might be the case.

Kelp does have phosphate ,so I doubt they can take it all out in manufacturing the concentrate or would want to in a soil fertilizer.
Though ,the Colorado State Univiersity notes insignificant phosphate , nitrogen and potassium for soil use; the amounts still might be significant for a tank.
It would be helpful to know the complete contents of the concentrate( can't find it) to ensure against higher than desireable levels of these and other perhaps potentially harmful elements to a closed system marine environment too. Since it's organic and comes fro the sea it may not be an issue for impurities but then some could come in in the manufacturing process. What resluts are you getting with it?

 

[Subsea]

Wern't sure if you were kidding. I thought it might be the case.

Kelp does have phosphate ,so I doubt they can take it all out in manufacturing the concentrate or would want to in a soil fertilizer.
Though ,the Colorado State Univiersity notes insignificant phosphate , nitrogen and potassium for soil use; the amounts still might be significant for a tank.
It would be helpful to know the complete contents of the concentrate( can't find it) to ensure against higher than desireable levels of these and other perhaps potentially harmful elements to a closed system marine environment too. Since it's organic and comes fro the sea it may not be an issue for impurities but then some could come in in the manufacturing process. What resluts are you getting with it?

Tom,
I agree with the generalization about phosphate being difficult to remove from the kelp plant. That was the basis of the joke about phosphate coming in with the air. On the label listed as Guaranteed analysis, phosphate is listed as zero. I will provide a link from the manufacture. Both a MSDS sheet and a guaranted analysis sheet.
Cheers,
Patrick

http://www.lillymiller.com/msds/ala..._Fertlizer_0.13-0-0.60_Item_No._100509476.pdf

I could not download the pdf, so I will list what is listed for Guaranteede analysis.
Major nutrients: 0.13 / 0.0 / 0.60

Detailed analysis:
N 0.130%
K2O 0.60%
Ca 0.18%
Mg 0.06%
S 0.035%
Cu 0.02%
Fe 0.008%
Mn 0.001%
Na 0.120%
Zn 0.002%

 

[Subsea]

Patrick ,thanks. I was asking Herring fish what he dosed and to waht level of NOe,since I'm intersted in his/her anecdotal observation..

BTW, Phosphate comes in with food ; some with substrate and live rock;not the air except with some dust perhaps.

BTW kelp concentrates are not much on nitrogen or phosphate per this link:


http://www.ext.colostate.edu/mg/gardennotes/234.html#kelpL


This is from it:





Liquid Kelp

Usually cold processed, liquid kelp will have higher levels of growth hormones than extracts. Some may also be enzymatically digested, making the growth hormones even more available to the plants.

<table class="bodyTd" align="right" border="1" width="450" cellpadding="3" cellspacing="1"> <tbody><tr> <td colspan="2">

Liquid Kelp​

</td> </tr> <tr> <td width="177">

Typical NPK analysis​

</td> <td width="202">

Negligible​

</td> </tr> <tr> <td>

Release time​

</td> <td>

Immediate – 1 month​

</td> </tr> <tr> <td>

Pros​

</td> <td>

Adds micronutrients ​

</td> </tr> <tr> <td>

Cons​

</td> <td>

Insignificant nitrogen, phosphorus, and potassium​

</td> </tr> <tr> <td>

Application​

</td> <td>

Mix 1 – 2 tablespoons per gallon of water ​

</td> </tr> </tbody></table>​

Tom,
I can not agee with your link. Nitrogen is 13% and potassium is 60%.
Patrick

 

[mhucasey]

Mhucasey, maybe not the best place to ask this but I noticed you use a 'conical settling tank' to your skimmer..
Can you elaborate or do you have a link?
Thanks!

Yep, Its a 16 gallon conical tank I got from an online source, all overflow water enters at the middle and is directed to the side, and then overflows out through a pipe in the side. In the below pic it all went to the skimmer, but that turned out to be too efficient, so there is a refugia chamber between the conical tank and the sump now, and I actively pull some of that water to the skimmer now. The Refugia chamber and sump are connected near the top, so whatever doesn't go to the skimmer overflows to the sump and is returned to the tank.

 

[herring_fish]

Patrick ,thanks. I was asking Herring fish what he dosed and to waht level of NOe,since I'm intersted in his/her anecdotal observation..

His.
Sorry, I didn't know that you really did want the information.

I didn't use a scientific methodology. I used stump remover from Lowes. Unfortunately, I just started with a spoon that you dish out brine shrimp eggs with. Of course I tested once or twice a day. I use one per day and kind of doubled it every day, off and on, until I got results. It took me about two weeks. The N levels never got high ... it got up to normal. When the scrubber got going, I stopped doing.

Also, in the past, I have pumped up the light to the scrubber when I was putting so much food into the tank that I couldn't see two inches into the tank, before the lights went off. Sometimes, I went into a over scrubbing condition. the corals liked it but when algal growth slowed, I added fish fertilizer by the cap full, right in the tank. My parameters stayed great.

 

[reefmutt]

Yep, Its a 16 gallon conical tank I got from an online source, all overflow water enters at the middle and is directed to the side, and then overflows out through a pipe in the side. In the below pic it all went to the skimmer, but that turned out to be too efficient, so there is a refugia chamber between the conical tank and the sump now, and I actively pull some of that water to the skimmer now. The Refugia chamber and sump are connected near the top, so whatever doesn't go to the skimmer overflows to the sump and is returned to the tank.

Very cool idea!
So you use this instead of filter socks, I assume.
Very efficient, indeed..
Thanks for posting.

 

[herring_fish]

Reefmutt:
That's great idea. I think. A settling tank"¦but I don't get it. Sorry
What are you settling?
Maybe, I could use one. Please explain more about it.

 

[2_zoa]

Reefmutt:
That’s great idea. I think. A settling tank…but I don’t get it. Sorry
What are you settling?
Maybe, I could use one. Please explain more about it.

Conical filters are used in a whole bunch of industry. Making bio diesel, food manufacturing, brewing, aquaponics, etc... I believe they're called radial filters on aquaponics systems.

I believe the pipe/valve on the bottom is his drain/clean out. It will catch any food or detritus or sediment. Basically anything that goes into the overflow should be captured in the conical filter.

It would be a great way to allow or not allow nitrates to build in the system. I had to add something that was on topic. Hehe.

Edit;
Just add a cone shaped bottom.
http://m.youtube.com/watch?v=RVzNcU8EnwU&feature=youtube_gdata_player

You can also make the water swirl inside or not. Like the vid. I can't post the pic I wanted to as I'm on my phone.

 

[tmz]

His.
Sorry, I didn't know that you really did want the information.

I didn't use a scientific methodology. I used stump remover from Lowes. Unfortunately, I just started with a spoon that you dish out brine shrimp eggs with. Of course I tested once or twice a day. I use one per day and kind of doubled it every day, off and on, until I got results. It took me about two weeks. The N levels never got high ... it got up to normal. When the scrubber got going, I stopped doing.

Also, in the past, I have pumped up the light to the scrubber when I was putting so much food into the tank that I couldn't see two inches into the tank, before the lights went off. Sometimes, I went into a over scrubbing condition. the corals liked it but when algal growth slowed, I added fish fertilizer by the cap full, right in the tank. My parameters stayed great.

Thanks for the information. I'm always intersted in anecdotal reports on this. What level of NO3 do you need to keep the scrubber in gear?