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[font color="#000080"]Hi,

What plants are good at obsorbing nitrate?
I'm not saying my nitrate level is high, i just want it to be as low as possible.
Currently, I have 15G with 5 guppies.
The tank is planted to 1/3 full with wisteria, java fern, amazon sword, ambulia, anubias nana, java moss.
I assume that the nitrate level is pretty low right now because the plants are obsorbing them.

What other plants are good at obsorbing nitrate?
How well will my plants do?
Does plants grow fast with or without nitrate?

Thanks,
Jimmy

Hi,
Actually there has been much discussion about nitrate
levels within a planted tank on other sites.
It seems that you want some nitrate and not zero nitrate.
It's a balancing act. More than a max of 15 and you
invite algae to over run the tank. Anything in the
zero range swings things the other direction and
again, algae steps in to fill a void. Somewhere
around a 9 or 10 seems to be optimum.

To absorb nitrate, directly, use floating plants.
They draw their nutrients directly from the water.
The other plants draw it through their roots, from
the gravel and while efficient, do it slower.

All that being said, with just 5 guppies in a 15G
tank, I very much doubt that you are anywhere near
the maximum, and that you should test, say weekly,
but not fret.

Frank


[span class="edited"][Edited by FRANK 2004-07-16 09:45][/span]

-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

To directly answer your question....I've found hornwort able to reduce nitrAtes from 40ppm to 20ppm in under 24 hours....however just like Frank said, you do need to be worried with too few nitrATes....I had BGA (cynobacteria) move into my 10 that was stocked (@the time) with 2 gold barbs and 3 young danios. After I started adding nitrATes in a measured way (rather than just overfeeding) I have seemed able to get it under control.

I'd also say the wisteria will help keep the levels low.

^_^

[font color="#000080"]Thanks guys.
So my nitrate level is considerably low right now
that's good, cause i want to get 2 kribs in the next couple of days
heard that they are kind of bit sensitive to high nitrate
Does ambulia obsorb nitrate as good as hornwort?

Hi,
The answer to your last question is no.
As I said in my reply to you
Quote:
To absorb nitrate, directly, use floating plants.
They draw their nutrients directly from the water.
The other plants draw it through their roots, from
the gravel and while efficient, do it slower.
EndQuote

Ambulia is a rooted, stem plant, and while it will
use nitrate, it will not consume it directly from
the water. Instead, it uses its roots to draw from
the substrate.
Hornwart, on the other hand, is considered a floating
plant and, as Babelfish mentioned, draws its nutrients
directly from the water.

Frank




[span class="edited"][Edited by FRANK 2004-07-17 09:57][/span]

-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

Ambulia is a rooted, stem plant, and while it will
use nitrate, it will not consume it directly from
the water. Instead, it uses its roots to draw from
the substrate.

I don't think this is right Frank. Ambulia is a stem plant. It draws it's nutrient in from the stem. Even though stem plants grows roots in the substrat, it is also capable of drawing netrients from the stem. Most stem plants that I have can grow roots from anywhere on the stem and will as their roots string through the water. This is why they can propagated by clipping and replanting.

Water flows into the substrate from the water column, it'
s slow but plenty for supplying nutrients to roots.

Many like to suggest plants prefer substrate nutrients, this is NOT true if the nutrients are present in the water column. There are numerous studies on nuttrient rich streams that showed this.

A plant will do root uptake of nutrients if there's not enough in the water column. If nuttrientsw run low in the water column, plants will also allocate more root growth in effort to supply the nutrients.

Both of these show strong evidence that plants, even if you cut the roots off, will still take the nutrients from the water column if they are supplied.

Substrate nutrients are a good back up in case something runs out in the water column though...

My vote is for water sprite for a good water column nutrient sponge.

But this 15gal tank most likely has no NO3 or very low.
Adding PO4, Traces, CO2 etc will increase NO3 uptake.

It is unlikely you saw a 20ppm 24h uptake due to the plants. Even at 6 w/gal and full CO2 andn other nutrients in good rnages the most you realistically hope for is perhaps 4-5ppm per 24 hrs. NO3 test kits are notoriously inaccurate. If you do tissue analysis and estimate the amount of growth you'd require for 20ppm per day uptake, I think you'll agree.
4-5ppm is pushing the limits.

Regards,
Tom Barr

Hornwort is great for absorbing nitrates

Hornwort can grow up to an inch in 24 hours (I've seen it grow at that rate for weeks on end in some of my own tanks)...If there is enough light CO2, and more individual hornwort plants it can really do some damage...say you had a 5g, with 6-7 WPG of light at 6700k or more, CO2, and about 60-70 large pieces of hornwort that had been growing at a decent rate in different tanks...you moved them all to that 5g at one time...it would probably go down quite a bit...especially if there wasn't any fish or anything in the tank to produce more ammonia, and thus nitrAtes. In this case it would probably go down more than 5ppm in 24 hours...

Just a thought....

I have seen many plants grow over an inch in 24 hours including ambulia, hygro. poly., bannana plant and many others when conditions are right.

It is unlikely you saw a 20ppm 24h uptake due to the plants... NO3 test kits are notoriously inaccurate.

I was curious about that...but all I had was the tests, and according to my color matching skills () it looked like a 20ppm change. It was a low light tank, no C02, but the hornwort had just been shipped, and was possibly hungry ?

^_^

I've been measuring my high light tanks for many years, I'v eonly seen one case using a Lamott test kit that ever exceeded more than 3-4ppm of NO3 per day.

The amount of growth is very deceptive, you need dry weight to measure the amount of N that is incorporated in the plant's tissues, genenrally weight to dry weight correlations are around 9:1.

The amount of plant biomass required for more than 3-4ppm per day is enormous. By mass, N is roughly 1.5% of the total weight of the plant's dry weight.

You can scale this up to figure out how much the plants must assimilate and/or store to get an idea of just how much growth is required.

I have plenty of plants that grow 1-2 inches a day, some even more.

But cheap kits will not give you good results.
This was discussed many years ago on the APD. You can check there for further reading on kits and NO3 uptake rates.

Many question the rates I gave at 3-4ppm being too high.
But there they are and the rough estimates in plant biomass also concurred well.

If you limit your tank with PO4 and keep it very low(0-0.2ppm), this slows the NO3 uptake down to around 1ppm a day.

Regards,
Tom Barr

Is there a particular brand of nitrate test that is most accurate? I work at a pet store and we sell the kits that we use when someone comes in to test their water. Would that be more accurate?

Does anybody have a picture of what hornwort looks like? I would love to get some for my tank, if it does lower nitrate.

Hi,
These are pictures of Hornwart:

http://www.azgardens.com/images/1bunch7.jpg
http://www.tropica.com/default.asp

Frank


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--