[VioletAqua]

Hello,


I'm planning a new aquascape looking for suggestions on what plants remove the most nitrates from the water. My nitrate levels seem to be getting high over the week leading up to my water change. Something to keep this a little more moderated would be nice.



Goals:

- maximize swimming space
- must tolerate medium/ slightly higher water flow rate around the tank.


Currently considering:
Hornwort
Duckweed. (not thrilled with the idea of this encase I want to remove in the future)



Issues in past:
Frogbit, water lettuce. I love the idea of having these 2 floating plants. Unfortunately I found they didn't like the flow I have my tank and prefer no/ low flow setups.



I like the idea of creating shade in the tank for the fish with a surface plant. My dwarf lily actually works very well at providing shade and can stand up to the medium flow rates. It will likely find its way into the new aquascape.



What plants do you feel remove the most nitrates from the tank and would be worth considering?

 

[Raith]

Add a barrier ring, make it out of plastic or whatever, put it into a corner opposite of the filter or whatever flow that you have, and you'll be able to keep your Frogbit, etc floaters.

 

[ElleDee]

The plants remove nitrate from the water column to fuel their growth, so any fast grower will fit the bill. Emergent plants are particularly effective because they have access to co2 in the air; this is also what makes floating plants so good. Fwiw I like salvinia and it can take being pushed around in a current, but not being submerged. If you can get away with feeding your fish less that will directly reduce nitrate production too.

 

[Roboto]

I like hornwort for this, but isn't the best in high flow rates since it's barely a floater. It also isn't the most pleasing visually floating in a tank in my opinion.
That being said, my tanks with hornwort floating have zero nitrates. I have a few tanks, and if I'm too busy and am going to miss a water change I drop some hornwort in my prettier display tanks and it reduces the nitrates quite well.

 

[Leeatl]

I use floaters and have Pothos and Arrowhead plants growing with the roots in the tank . Both are good at eating nitrates .

 

[ahem]

It would interesting if someone did an experiment measuring nitrate levels and the effect of different species. Until then everyone is guessing at what likes nitrates. It is a reasonable guess to use anything that grows fast.

Stem plants like Rotala's grow very fast, I have to chop mine weekly or they will bend at the surface and shroud the rest of the tank.

For floaters I use Salvinia minima (water spangles). Spangles appear to multiply as fast a duckweed (super fast!) but is MUCH easier to keep control, I can net every spangle in my 50 gallon in a couple minutes vs duckweed that you may never get every last bit. In that tank, I will reduce spangles down to less than 10% coverage of the water surface, within two weeks it will have multiplied to cover the entire surface. I have to remove several clusters with every daily water change to keep it in check. I put a few in a shallow turtle tank and within a couple weeks it over took that tank.

Floaters are easy to use for nutrient control because there is no trimming. You just remove them when you get too many. Give some to friends. They also create shade that can be used to as an algae reduction strategy if there is a problem with that. The flip side is that since they are exposed to air, they respire that way and do not oxygenate the water. In a thick cover they can impair gas exchange, make sure you have good filtration or keep an open section.

However, be careful with throwing away some fast growing floaters like Salvinia minima as they can severely damage local ecosystems. In some states they are illegal.

 

[mourip]

I use floaters and have Pothos and Arrowhead plants growing with the roots in the tank . Both are good at eating nitrates .

+1 for Pothos and also Anthurium.

As mentioned above overfeeding is a huge culprit.

 

[Griznatch]

I have a pretty big Pothos in back corner of my 75, and my wife has both Pothos and a big Philodendron hanging out out of hers. They work really good for us.

We also have duckweed, but it doesn't do well in high flow.

 

[en7jos]

+1 from me for salvinia minima as a fast growing floater that is super easy to remove when needed.

I have it in all my tanks; in some it multiplies from 10-90% surface coverage in only a week or two, in others it's more like 10-30% in the same period. Given that these tanks are identical (identical shrimp tank setups in a row), and that I have rarely measured any significant nitrate or phosphate in water tests despite fertilising at 150-200% of Seachem's 'starter dose', I'm pretty confident that the salvinia are mopping up any excess nutrients in each tank.

 

[[email protected]]

I have really great results with wisteria which I float. The roots hang down and suck up nitrates. It grows so well I give it away with corkscrew val I sell on reddit. I have pothos in one tank that works as well

 

[Oughtsix]

I will add to the Pothos recommendation. We put floating Java Moss along with the terrestrial Pothos in my daughters axolotl tank and it grows very fast for us, consuming lots of nitrates in the process. It gets a healthy amount of light though. I don't know how it would do with less light????

 

[en7jos]

Floating java moss, now there's any interesting idea.... A whole new playground for the shrimp!

 

[osp001]

It would interesting if someone did an experiment measuring nitrate levels and the effect of different species. Until then everyone is guessing at what likes nitrates. It is a reasonable guess to use anything that grows fast.

I've pondered exactly how to run this experiment, and it is fraught with experimental variables. What constitutes "a plant"? Do we determine nitrate sequestration on the basis of fresh (wet) weight? Number of "sprigs" or plants would be useful, as few (if any) people say "I have 100 grams of plants" in their tank, but number of plants matters little because plants vary in size, of course.


Establishment matters, as does the permeability of the substrate, particularly for plants that feed mainly at the root level. Light levels are variable, and pretty much no matter what size tank is used (and, therefore, depth of planting), someone will find flaws with the experiment.


I do note a number of people using pothos etc. in the system for absorbing nitrate, with one prominent YouTuber using variegated plants- talk about shooting yourself in the foot!


Also not considered by many people: direct nitrate sequestration. Some plants are intrinsically high in nitrate. It might be useful to try some of these immersed plants that gobble up a disproportionate amount of nitrate; much of the nitrogen consumed ends up in proteins, but there are some plants that have way more nitrate than others (arugula!) and growing them hydroponically in a tray on top of the sump or whatever might be quite useful.

 

[ahem]

I've pondered exactly how to run this experiment, and it is fraught with experimental variables. What constitutes "a plant"? Do we determine nitrate sequestration on the basis of fresh (wet) weight? Number of "sprigs" or plants would be useful, as few (if any) people say "I have 100 grams of plants" in their tank, but number of plants matters little because plants vary in size, of course.


Establishment matters, as does the permeability of the substrate, particularly for plants that feed mainly at the root level. Light levels are variable, and pretty much no matter what size tank is used (and, therefore, depth of planting), someone will find flaws with the experiment.


I do note a number of people using pothos etc. in the system for absorbing nitrate, with one prominent YouTuber using variegated plants- talk about shooting yourself in the foot!


Also not considered by many people: direct nitrate sequestration. Some plants are intrinsically high in nitrate. It might be useful to try some of these immersed plants that gobble up a disproportionate amount of nitrate; much of the nitrogen consumed ends up in proteins, but there are some plants that have way more nitrate than others (arugula!) and growing them hydroponically in a tray on top of the sump or whatever might be quite useful.

I had not thought about that nitrate is important in protein synthesis and that possibly plants that are high in protein, like duckweed, may need more nitrogen than other plants. It's an interesting concept that could net some interesting hypothesis in nitrate usage.