Different Nitrate levels and their effects

[Twocoralsonetank]

This is pretty simple, but just don't think I really understand.

Is there a difference between .50 NO3 and 2 NO3?

Is there a difference between 2 NO3 and 10 NO3?

I have read multiple forums that state 0 NO3 is bad which I think we all understand now. So you need to have very little NO3 in your system, even 1 NO3 is good enough. So if you have NO3 in the water it doesn't matter if its 2 or 10 correct? Or is there a difference?

My tank struggles, I mean really struggles below 1. I mean the bases start to turn white and polyp extension is effected. Once I start getting up above 2 I can see the positive effects. But wouldn't it all be the same as long as it available? Or is the concentration important as well?

 

[Randy Holmes-Farley Verified Community Expert]

Obviously there's a difference. Whether you have any organisms for which those differences are significant is a different question, and far harder to answer. It also depends on several other chemicals in the water, since there's a strong interplay between them.

For example, if you have very low phosphate, then phosphate may be the limiting factor for growth for some organisms, and it wouldn't matter if the nitrate was 0.1, 1, 10, or 100 ppm.

But if in that same tank you have 1 ppm phosphate, then low levels of nitrate (say 0.1 or 1 ppm) might become the growth limiting factor.

And then again, if there are sufficient organic sources of nitrogen (such as amino acids present, then even 0.1 ppm nitrate might be plenty, or even 0.0000001 ppm.

Such comments can apply to many ions in the water, not just N and P (also iron and others).

So there is no single magic number that is optimal in all situations EVEN for a given single organism.

That said, many reefers have found that nitrate in the 0.5 to 10 ppm range seems to strike a good balance for many organisms in their aquaria.

 

[Twocoralsonetank]

Thanks Randy,

It seems so easy but so complex at the same time. As a raise my NO3 I continue to get positive results. Hanna ULR test shows low PO4 but I know its there because I got some hair algae in the overflow box.

Does light have an effect on the consumption of NO3? If I run a strong PAR rating should I up the NO3 in the tank?

 

[Randy Holmes-Farley Verified Community Expert]

Thanks Randy,

It seems so easy but so complex at the same time. As a raise my NO3 I continue to get positive results. Hanna ULR test shows low PO4 but I know its there because I got some hair algae in the overflow box.

Does light have an effect on the consumption of NO3? If I run a strong PAR rating should I up the NO3 in the tank?

I wouldn't assume you should keep it higher because light is higher, but consumption will often be higher if organisms are growing faster in more light.

 

[Twocoralsonetank]

Thanks Randy, ill keep dosing and watch the corals response and find that happy spot.

 

[Twocoralsonetank]

Randy is it normal for some corals, mostly green colored, to go brown after the NO3 dosing?

 

[Randy Holmes-Farley Verified Community Expert]

Randy is it normal for some corals, mostly green colored, to go brown after the NO3 dosing?

Increased zoox levels in corals can be a side effect of elevated nutrients, and more zoox can cause a browner look..

 

[SaracensRugby]

Randy, I have never seen nitrates above 2 in my tank (during cycle), and over the last 9 months nitrates are basically undetectable based on salifert tests. I currently do weekly 10% water changes, and am thinking of decreasing that to 5% or less and take a watch and we approach. I currenltly have a little bit of GFO and carbon in a reactor and swap it out every month. Some of my SPS look good and are slowly growing, others seem stalled with so-so color. Phosphate doesn't register, although I know it is there based upon GHA growth in my fug. Would you recommend backing off the total amount of water I am changing out on a monthly basis to help raise nitrates a bit? It seems like everyone has a nitrate problem but me. Thanks in advance!