Plants that consume heavy amounts of Nitrates?

[Ben Ellison]

I currently run several planted tanks and constantly seem to have above the desired Nitrate. I run around 80-120 PPM. I can obviously water change it off and do but I feel I am kinda wasting my ferts by reducing the Nitrates only to redose. I am under the opinion that just because the nitrates is high the other building blocks the plants need can be low. What id love to do is get nitrates consumed so that when I go to add more I dont need to change out 40% of my tank to be able to put a squirt or 2 in. I run mostly Anachris, Swords,Frogbit and Crypts. Does anyone know of some nitrate hogs I could add in?

[Daniel]

Hornwort

[Ben Ellison]

Ok ill look into getting some tommorrow

[definetlynotanoob]

Pogo octopus does well for me . Grows fast and it’s easy to propogate

[etheridgej]

Duckweed, but you’ll never get rid of it 😂

[Sleepy]

Pretty much any floating plant which would also include hornwort, wisteria, water sprite, pogostemon octopus.

[Alesha]

From my (limited) experience, if you can get some plants that grow above the water surface with their root immersed, it seems to gobble up nitrites too. I tried Pothos and it has worked really well for me!

[Jessica.]

Pothos is my go-to nitrate hog. But if you're already running frogbit & anacharis and still getting up to 120 ppm, you'll probably need a lot of pothos or whatever other nitrate sink plant. Also worth noting that some studies have shown high nitrate levels inhibit growth of select species of plants. (I'm not saying this is the case, I'm just pointing out it's been theorized and some studies support it in select species of plants, including salvinia which's growth was inhibited by 40% at 32ppm nitrates.) 

Another solution would be to dose a fert that doesn't have nitrates, or to buy some micro ferts and potassium phosphate. The seachem line could accomplish this, or nilocg sells convenient and cheap powdered ferts.

I'm curious, what's causing the nitrates to get to 80-120? Seems wildly high to be coming from an all in one. 

Hope you'll keep us posted. It'd be great to know if one of these options fixes the issue for you. 

[MattyIce]

25 minutes ago, Jessica. said:

Pothos is my go-to nitrate hog. But if you're already running frogbit & anacharis and still getting up to 120 ppm, you'll probably need a lot of pothos or whatever other nitrate sink plant. Also worth noting that some studies have shown high nitrate levels inhibit growth of select species of plants. (I'm not saying this is the case, I'm just pointing out it's been theorized and some studies support it in select species of plants, including salvinia which's growth was inhibited by 40% at 32ppm nitrates.) 

Another solution would be to dose a fert that doesn't have nitrates, or to buy some micro ferts and potassium phosphate. The seachem line could accomplish this, or nilocg sells convenient and cheap powdered ferts.

I'm curious, what's causing the nitrates to get to 80-120? Seems wildly high to be coming from an all in one. 

Hope you'll keep us posted. It'd be great to know if one of these options fixes the issue for you. 

I checked the abstract on the study on salvinia, probably not going to pay 36 for the full study, but from the abstract it seems to imply that Salvinia mostly uses Ammonia for its metabolic processes, and that it suffers with just nitrates and no ammonia. 
 

Nitrogen nutrition of Salvinia natans: Effects of inorganic nitrogen form on growth, morphology, nitrate reductase activity and uptake kinetics of ammonium and nitrate - ScienceDirect

WWW.SCIENCEDIRECT.COM

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In this study we assessed the growth, morphological responses, and N uptake kinetics of Salvinia natans when supplied with nitrogen as NO3−, NH4+, or …

"Plants supplied with only NO₃⁻ had lower growth rates (0.17 ± 0.01 g g⁻¹ d⁻¹), shorter roots, smaller leaves with less chlorophyll than plants supplied with NH₄⁺ alone or in combination with NO₃⁻ (RGR = 0.28 ± 0.01 g g⁻¹ d⁻¹). Ammonium was the preferred form of N taken up. The maximal rate of NH₄⁺ uptake (V_max) was 6–14 times higher than the maximal uptake rate of NO₃⁻ and the minimum concentration for uptake (C_min) was lower for NH₄⁺ than for NO₃⁻."



also reading some of the comments from the forum link provided, a person commented on biologic turning ammonia into nitrates before salvinia has a chance to use it causing their nitrates to run high.

Now I kind of want to experiment with Salvinia while cycling a tank, with a crashing tank, and with no filter tanks.

[ange]

My current favorites are: hornwort (I have both C. submersum and C. demersum and currently don't know which one does a better job, though C. submersum sheds significantly less when transitioning to a new tank), Amazon frogbit (saved my shrimp tank from nitrate-fueled algae blooms), and giant duckweed.

I've tried pothos as other have but for whatever reason it fails to root in 50% of the setups I attempt adding it to. I know a lot of people have success with it so I've always taken it as a "me" thing and will continue suggesting it to others as something to try.

[Daniel]

The reason I mentioned hornwort above was I thought I read somewhere that it was used in some wastewater treatments @KBOzzie59 can check me on this.

But after reading @Jessica. and @MattyIce post's above I went poking around on Google and found this paper:

Responses of bacterial community structure and denitrifying bacteria in biofilm to submerged macrophytes and nitrate

WWW.NCBI.NLM.NIH.GOV

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Submerged macrophytes play important roles in constructed wetlands and natural water bodies, as these organisms remove nutrients and provide...

After spending 3 minutes speed reading it, I think one of its conclusions is although most denitrification is thought to occur under anaerobic conditions, plants (aquatic macrophytes in the paper's lingo) can provide a large surface area for attached biofilm (epiphytic microbes in their lingo) thereby providing a 'pathway for the biological modulation of nitrogen'. Yay! That's what we want.

The density of the Nitraspina, Nitrospinacacae, and Nitrospria bacteria (the famous beneficial bacteria) was much greater on the surface of plant leaves than either gravel or plastic (I didn't know that, I thought all surface area was the same, apparently plants enter into a beneficial relationship with bacteria and help provide the oxygen and organic carbon the bacteria needs) . Obviously plants with greater surface area to leaf ratios like hornwort or Eleoacharis (hair grass) will provide greater opportunities for biofilm.

Duckweed roots get a brief mention. Almost none of the bacteria could be cultured but was detected through DNA analysis.

In summary, one of the reason hornwort is so good is that hornwort has a lot of surface area for the beneficial bacteria to grow on. And not just any old surface area but plant leaf surface area, the bestest kinda of surface area if you are a beneficial bacteria.

 

[KBOzzie59]

@DanielYep I've seen hornwort at some plants and a bunch of duckweed.  I suppose it just depends on what temperate zone the plant is in.

 

The Use of Aquatic Plants to Treat Waste Water | Fourth Corner Nurseries

FOURTHCORNERNURSERIES.COM

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by Cristian Frers, Senior Environmental Manager and Consultant; Translated by Veronica Wisniewski We are publishing this article in this edition as an...

 

 

[Seized]

Hornwort and water sprite really suck up nutrients very well. Another good one is to use water lettuce.

[Marnol D]

hornwort is very good at using nitrates (however it can also shed tons of little leaves and create a mess). I started running CO2 in my tanks and went from 40+ nitrates down to 5-10 and my plants started taking off. Your plants could just be missing some nutrients that your arent dosing. (it may be hard to find out which ones) 

 

Hornwort grows super duper fast and depending on how much light it gets depends on how the leaves grow.