Best nitrate removers (fast growing plants)

[toothgrinder]

Hello, I am looking for ideas for some of the fastest growing plants, weeds basically to add to my 75 gallon tank. It is already what most people consider overstocked but before I added the dojo loaches the nitrates stayed very low. My problem now is the dojo loaches are still young yet and they’ve already brought a significant bioload to the mix. I have no problem doing big water changes frequently MOST of the time, but I travel for work and while my girl can take care of feeding and water changes for the smaller tanks, I can’t expect her to service my 75 and 150.

I know from experience duckweed grows super fast and would be exactly what I’m asking for, but i had it in here before and it covers the entire surface within a week or two. That’s with me pulling huge handfuls out every water change. I fear it steals all the light from the plants below. 
 

Current stocking in case anyone’s curious- 2 six inch dojo, 2 three inch gold dojo, 8 bronze Cory, 6 albino Cory, 7 adolfoi Cory, 4 trillineatus Cory, and something like 15-20 nerite snails. Jungle Val, Italian Val, corkscrew Val, bacopa, Anubias, a melon sword plant, small amounts of dwarf hair grass that will probably not take off into the carpet that I want it to, baby tears on driftwood, and some mosses. I’ll probably be forced to remove two of the four dojo’s when they grow bigger. I might have a pond by then or worst case I have friends who would want one.

I know I’ll never pull off a wahlsted with this stocking especially since I will be adding more corydora in here, but I need the nitrates to slow down a bit. Any input is appreciated!

The picture is freshly trimmed, the jungle Val reaches the top of the water and folds over once a week. Also the layout is little different now basically there is less rock and more room for plants.

 
Here’s how it looks when I’ve been away for a week. Sounds like I’m answering my own question, as my jungle Val just explodes constantly but I would like other plants that grow just as fast if not faster.

Edited December 10, 2020 by toothgrinder
Added second photo

[FrozenFins]

In most of my aquariums I have a feeding ring full of floating plants, this helps contain the plants to one spot so its not covering the entire tank.

I don't like duck weed because of how small it is. But amazon frogbit is great!

Guppy grass is nice to, but... doesn't have a very nice asthetic look to it.

 

[toothgrinder]

3 minutes ago, James Black said:

In most of my aquariums I have a feeding ring full of floating plants, this helps contain the plants to one spot so its not covering the entire tank.

I don't like duck weed because of how small it is. But amazon frogbit is great!

Guppy grass is nice to, but... doesn't have a very nice asthetic look to it.

 

The feeding ring is a nice idea but it might be counter intuitive to my goal of having plants just exploding in there. I heard guppy grass actually prefers low light and grows slower with good light, from one of corys videos or maybe it was LRB aquatics? My tanks got two 48” leds so definitely not low light! But, is it super fast growing regardless, in your experience? 

[FrozenFins]

3 minutes ago, toothgrinder said:

The feeding ring is a nice idea but it might be counter intuitive to my goal of having plants just exploding in there. I heard guppy grass actually prefers low light and grows slower with good light, from one of corys videos or maybe it was LRB aquatics? My tanks got two 48” leds so definitely not low light! But, is it super fast growing regardless, in your experience? 

Its not as fast as the duck weed, but its still a weed so still somewhat fast

[Marnol D]

Ive heard hornwort loves nitrates. I’ve had it and it grows super fast. I made the mistake of removing it all due to it shedding needles but now I want it back. Luckily I found a tiny sprig I missed and hopefully I can get it to grow back. 

[Daniel]

There is some research that shows fast growing plants like hornwort and water lettuce are the best at removing nitrates

[gardenman]

Pothos could do the job with just their roots in the water. Floating plants would have some benefits as well as drawbacks in your tank. They grow fast. They won't compete for the carbon dioxide in the water column as they'll pull all they need from the air. They're easy to remove as they overgrow the tank. They're cheap. And they're pretty tough little plants.  The chief drawback is they'll block the light from your planted plants. I'd probably try to focus on larger floating plants to remove nitrates. If you weigh a water hyacinth that covers a square foot of the tank and duckweed that covers a square foot of the tank the water hyacinth would likely weigh a lot more. Why is this important? A lot of a typical water hyacinth's growth is above the water. It's a bigger, bulkier plant that would therefore have more plant that needs to be fed. Nitrates in your water is its food. A square foot of water hyachinth or water lettuce should therefore consumer more nitrates than a square foot of something smaller that sits only on the water surface. (Or so I'm assuming.) If you opt for a floating plat the bigger ones like water hyacinths and water lettuce would be my recommendations. They're far easier to control than duckweed and they have more mass to absorb more nitrates. I'll add a photo of a water hyacinth and it's three babies below. It's adrift in the sea of duckweed in my thirty high. A big plant is far easier to weed out than lots of little ones. (I have modified an Odyssea Clean 100 Surface Skimmer to vacuum up duckweed however and it works pretty well. Just enlarge the openings on the three sides of the skimmer cut to accept duckweed and you've got a duckweed vacuum cleaner.)

[CanadaAmanda]

Indian water fern, cabomba, moneywort are all pretty easy to grow and seem to grow quickly.  Some people do the indian water fern as a floating thing and others plant it in the substrate, it exploded during an ammonia spike I had, so I'd say it'll soak up nitrates pretty nicely, but the leaves will melt back if those nutrient levels drop.  Guppy grass is great if you want bits of guppy grass everywhere in your tank.... I like it for baby fish but I'm going to yank it out of my tank except for the breeder net the babies are in... it's just too irritating.  I have an artificial plant that most of it sort of gets caught in and that looks good, but bits make their way out and get caught in all the other plants, filter, decor.

Edited December 11, 2020 by CanadaAmanda

[Mmiller2001]

Hygrophila Polyspermy and Frogbit come to mind. Hornwort has too many negatives in my opinion.

[ccurtis]

Water wisteria is a pretty fast growing plant and seems to do a good job. I have to trim mine weekly.  

[Colu]

Vallisneria spreads l a weed in my tanks 

[Sapere_Ceta]

You’d probably really enjoy Myriophyllum elatinoides! It is easy and quick growing, with a soft and beautiful appearance. There are some great studies on the plant in relation to absorbing nitrogen. 
From “Myriophyllum elatinoides growth and rhizosphere bacterial community struggled under different nitrogen concentrations in swine waste water”: 

“N concentration in roots were higher than that in stems snd leaves under high N conditions. TN (Total nitrogen) and NH4+ (Ammonium) removal efficiencies reached 84.0% and 87.2% respectively.” 

Swine wastewater (or waste water in general) has very high nitrates and nitrites. So plants can be used to try and counteract the negative effects of the wastewater. Although this doesn’t specifically mention nitrates and nitrites, both are factored in and TN was used  to cover everything broadly.