Nitrates in reef tank?

[BeejReef]

Do you run a refugium?
I mean, if it's not broken.... ofc.

Still, if it's something that you are going to attempt to reign in, a golf-ball sized hunk of chaeto and a cheap horticulture LED in the sump would give you a very gradual method of lowering them. You'll be scooping chaeto out with a pitchfork with 160N and .25P!!

 

[Paul Ketchum]

Had the same issue for years, Old test kits lied, indicated No3 fine...my softies did okay, with nothing else ever surviving, and no amount of filtration helped. If you feel strongly about reducing nitrate, try carbon dosing. Start SLOWLY as per http://reefkeeping.com/issues/2008-08/nftt/index.php. This works but do it this way! Recommend NYOS-nitrate for testing until down into the teens then move to Red Sea. Buy 2 NYOS kits, you will need them. That said if you are happy with just softies, carry on you have a fine looking tank.

 

[Belgian Anthias]

Had the same issue for years, my softies did fine, with nothing else ever surviving and no amount of filtration helped. If you feel strongly about reducing nitrate, try carbon dosing. Start SLOWLY as per the instructions. you will need to test every other day until you have a understanding of that rate of drop, and then, as you near your desired level, you will need to reduce the dosing amounts. Shoot for a reduction of 3 to 4 ppm per week. Recommend NYOS-nitrate for testing until down into the teens then move to Red Sea. Buy 2 NYOS kits, you will need them. That said, if you are happy with just softies, carry on.

This is a system in balance.!
Vodka dosing will mess up this balance as ammonia nitrogen and other building materials now used by slow growing autotrophs will be used up by fast growing heterotrophs.
This system has a balanced nitrification - denitrification capacity and a balanced nitrogen consumption as the level stays steady, although this balance is found at a high nitrate level. Vodka dosing will remove this balance as nitrifiers and photo-autotrophs will be outcompeted for ammonium and other building materials. This will also effect the coral holobiont which is used to the present ammonium and other building materials availability.
If vodka dosing ( adding carbohydrates) is used for lowering the nitrate level one must be aware that fast growing heterotrophic r-strategists do prefer ammonia nitrogen for growth and will only use nitrate nitrogen as an emergency measure while reducing and limiting log phase.

The nitrate level may drop because other live forms are forced to use nitrate-nitrogen, which may be beneficial .
If the consideration is made to much nitrate-nitrogen is present in the system which has no use and may be removed, the nitrogen should be removed from the system and not stored into biomass which may be recycled and build up in the system. A skimmer removes vodka produced TOC very selective leaving most DOC in the system ( +- 35% may be removed.
Vodka dosing needs building materials for fast growth. As this system is in balance and growth is limited by other factors as nitrogen availability these building materials may not be freely available and will be retrieved in competition with other and slower growing live forms including corals.
Vodka is easily overdosed as doses are generally based on the nitrate level and not on ammonium availability. Any dose will be an overdose in this balanced system.

 

[Fin-up reefing]

You shaking the bottles for 30 seconds before you use em and shaking the test kit for 60 seconds ?

I find it hard to believe its at 160.. fish would get nitrate poisoning aka brown blood and die from nitrates that high

I followed instructions properly

 

[Fin-up reefing]

What tests are you using?
Some tests get it all wrong.

API

 

[Fin-up reefing]

Do you run a refugium?
I mean, if it's not broken.... ofc.

Still, if it's something that you are going to attempt to reign in, a golf-ball sized hunk of chaeto and a cheap horticulture LED in the sump would give you a very gradual method of lowering them. You'll be scooping chaeto out with a pitchfork with 160N and .25P!!

Will give it a try

 

[Belgian Anthias]

I find it hard to believe its at 160.. fish would get nitrate poisoning aka brown blood and die from nitrates that high

In the early days 1000 mg NO3/l was measured in public marine aquaria without any signs of discomfort for the fish. 200-300ppm was considered normal for fish only marine tanks.
For marine shrimp aquaculture 220 ppm is the limit for normal growth rate. For marine aquaculture in general 90-100 ppm is considered a safe level for max growth rates for most fish species.

160 ppm nitrate = +- 40 ppm NO3-N

 

[Belgian Anthias]

Will give it a try

As you do not have algae growth for the moment, how fast chaeto will grow? Where the building materials needed will be retrieved from? Any idea how much chaeto one has to grow to harvest 20 grams of nitrogen?

Why the nitrate -nitrogen is not consumed for the moment by the photo- autotrophs ?
If cheato is used to lower the nitrate level one probably has to reduce the skimming rate to provide more nutrients.
Changing the skimming rate may change the nitrate-nitrogen consumption, will change the present balance.

 

[Stigigemla]

I remember from the early days that it was very hard to introduce new fish in old tanks. But then came the nitrate test and it was suddenly much easier. I was recommended to go under 125.
Information source: Coffeecorner at the LFS.
Only nitrate test was Merck multi sticks. Readings for 60, 125, 250, 500 and 1000 if I remember right.

Aside from that it is difficult to remove so much nitrate with a carbon source without depleting the phosphate. So be careful. It is a possibility that the zoas will love the carbon source. (More bacteria in the water to feed from).

 

[dwest]

I would certainly get better test kits to start. I use a salifert nitrate and Hannah ulr phosphate and recommend both. I would not carbon dose, or do anything to reduce nutrients, until then.

Very nice tank!

 

[Paul B]

My reef ran 160 nitrates for years with no problems and I had many of the same corals you have. But your tank looks nicer than mine.

 

[Dom]

Am I doing something wrong?

If you are happy with your results... if you are happy with what you see... if your inhabitants are happy, then the answer is "nothing".

 

[Dom]

Is it possible your corals are consuming it so quickly that it isn't an issue?

I would think, if that were the case, he wouldn't be reading 160.

 

[Dom]

If is isn't broken, don't try and fix it.

 

[Bxr126]

Bro.... If you are happy with it leave it alone!

 

[Belgian Anthias]

This is a system in balance.!
Vodka dosing will mess up this balance as ammonia nitrogen and other building materials now used by slow growing autotrophs will be used up by fast growing heterotrophs.
This system has a balanced nitrification - denitrification capacity and a balanced nitrogen consumption as the level stays steady, although this balance is found at a high nitrate level. Vodka dosing will remove this balance as nitrifiers and photo-autotrophs will be outcompeted for ammonium and other building materials. This will also effect the coral holobiont which is used to the present ammonium and other building materials availability.
If vodka dosing ( adding carbohydrates) is used for lowering the nitrate level one must be aware that fast growing heterotrophic r-strategists do prefer ammonia nitrogen for growth and will only use nitrate nitrogen as an emergency measure while reducing and limiting log phase.

The nitrate level may drop because other live forms are forced to use nitrate-nitrogen, which may be beneficial .
If the consideration is made to much nitrate-nitrogen is present in the system which has no use and may be removed, the nitrogen should be removed from the system and not stored into biomass which may be recycled and build up in the system. A skimmer removes vodka produced TOC very selective leaving most DOC in the system ( +- 35% may be removed.
Vodka dosing needs building materials for fast growth. As this system is in balance and growth is limited by other factors as nitrogen availability these building materials may not be freely available and will be retrieved in competition with other and slower growing live forms including corals.
Vodka is easily overdosed as doses are generally based on the nitrate level and not on ammonium availability. Any dose will be an overdose in this balanced system.

To assimilate 1 gram of nitrogen +- 8 grams of bio-mass must be produced.

 

[Stigigemla]

If You change 10% each week the nitrate will be 10% of todays value in 22 weeks if no new nitrate is added.
I think a refugium with Chaetomorpha can be a good solution but even slower. I dont recommend larger water changes than 10% because that will be a big enough change in the values to irritate some corals.
I think a lot of stone corals will not survive the sudden transition to Your water. Even softies will need some acclimation time.

 

[Belgian Anthias]

I think a refugium with Chaetomorpha can be a good solution but even slower. .

I doubt it would be a good solution for this system.
As there is limited algae growth in the system, how cultivating Chaeto may lower a high nitrate level? As the nitrate-nitrogen is not used up by photo-autotrophs at the moment, Chaeto must be able to outcompete other users for the same building materials? Even when able to outcompete other users, to lower the nitrate level more building materials are needed since they are used up by present activity.
Cheato is very effective to limit algae growth when to much nutrients are available which obvious is not the case here.
Chaeto is not suitable to lower the nitrate- nitrogen content only as nitrate nitrogen availability may increase because other building materials are limited available for growth. A skimmer removes part of the available building materials constantly but selective, leaving most ammonium to be used.
If Chaeto are able to outcompete other users ( which would be remarkable) , it will be autotrophs, and the existing balance will be changed.

 

[Stigigemla]

I believe its the fishes that hold the algae back.

 

[Lasse]

As I know it - Chaeto has the enzyme that´s needed for conversion of NO3 into NH3/NH4. Further on - macroalgae often have the N-P ratio between 50 - 80 to 1 (50 to 80 atoms of N to 1 atom of P) IMO - a chaeto refugium would be great if you want to lower both NO3 and PO4. But as many have state in this thread - if your aquarium have no problems at all - why change and lower the nutrients. If you want to lower them - do it slowly, slowly and be sure that you do not run down to 0 PO4

Sincerely Lasse