low nitrate level

[Andrewtfw]

At Aquafest, I recall speaking with a member of GWAPA regarding nitrates. I was stating that my nitrate level was zero all the time. I think he said this is common but not good for the long run and that I should be adding supplemental nitrogen to the tank.

If you are a plant person and can explain whether or not this is true and why, please help increase my level of knowledge by doing so.

-Andrewtfw

 

[iamzrad]

Well, technically speaking, the air we breathe is made up of around 78% Nitrogen, 20% Oxygen and 2% other gases.
So for plants to thrive, whether it be aquatic plants or not, Nitrogen is a big factor.
But for aquatic plants, since Nitrogen is a gas, it needs to be formulated into a "fixed" substance when mixed with Oxygen. And that is exactly what Seachem Flourish Nitrogen liquid fertilizer does. Takes the Nitrogen from an Ammonium form and makes the Nitrate available for plants.

From what I have been told and experienced, a Nitrate level of 20-35ppm is safe for planted tanks but should always be regulated and maintained.
But to get to that level, the Nitrates need to be acclimated and once achieved must sustain the level at all times.

This is probably all I know about the Nitrate contribution to planted tanks, I'm sure others may have more knowledge than me.

 

[Andrewtfw]

Phil- thanks for sharing your knowledge. In the event that the nitrate level remains at zero, what problems will occur?

 

[chris_todd]

Phil- thanks for sharing your knowledge. In the event that the nitrate level remains at zero, what problems will occur?

Andrew, I'm no expert at recognizing the symptoms of various nutrient deficiencies in aquatic plants, so this post on Aquatic Plant Central has been very helpful to me:
http://www.aquaticplantcentral.com/forumapc/fertilizing/62876-plant-deficiency-picture-diagram.html

Plants need nutrients just like fish or any other living thing, and Nitrogen (either in the form of ammonia or nitrate) is one of the more important ones. Trying to grow aquatic plants in a zero nitrate tank would be like feeding an omnivore an entirely vegetarian diet - they'll do OK for a while, but eventually begin to deteriorate and show health problems.

 

[lonlangione]

Andrew first thing I would do is get a new No3 Nitrate test kit. It would seem to me that it would be extremely rare that you would have a 0 nitrate level.

Lonny

 

[Andrewtfw]

Hi Lonny,

I know the kit is good. It is only a few weeks old. I am using it on all of my tanks and it reads the nitrate level on all accurately. I have one plant tank that occasionally registers zero for nitrates. I have since been adding seachem's nitrogen and the nitrate level has come up to 5ppm and is holding there.

 

[hollyfish2000]

Andrew and I have been having this discussion. My relatively new planted tank is very plant heavy and not all that stock heavy and I have yet to register more than 5 pm nitrate at any time in the past two months. For that reason, I'm only doing limited water changes. Not sure if that's a correct approach or not. I'm not dosing nitrogen, but am dosing Flourish, which I believe has nitrogen as a component...

Nice graphic referenced above. According to it, I have a potassium deficiency . . .

 

[ingg]

I'm always zeroed out on nitrates in the water column, but that is with mineralized soil, different system.

In a more traidtional planted tank, no, you don't want to zero out nitrates.

Why? Here's a simple reason - you need three basic things for plants to grow. Carbon source (Co2), light, and nutrients.

Of the nutrients, nitrates are the consumed the fastest.

Plants need all three things to be able to grow. Without all three, growth rates are constrained to the availability of the lowest of those three resources.


Algaes, however, adapt much more readily to growing with only some of those things, and not all - taking advantage of the slowing growth of the plants to "eat" the oither abundant resources.

Many algaes thrive in scenarios of excess iron, or low nitrates in general, or excess potassium, or excess organics, etc. If the plants shut down growth due to no nitrates, these other scenarios are very likely, so....

You'll see two common questions when folks get algae explosions. What are your nitrate levels, what is your CO2 level (and the third being what is your lighting level). This is why.

 

[Andrewtfw]

ingg- Thank you very much for clearly explaining the need for nitrates in the planted aquarium. Is there a specific ppm range that is needed for the plants?

 

[ingg]

In a typical water column dosing tank, you'd want to keep them over 10ppm, and usually under 30ppm. It all depends on lighting, how fast the engine goes - really high light tanks can mow through nitrates, while low light tanks typically get what they need from fish mulm.

Slowly ramp up nitrates until you see it not dipping below 10ppm is my advice. Then you'll know there is a constant source, but no danger to nitrate sensitive livestock.

 

[Andrewtfw]

I checked the nitrates last night. They were at 5ppm. Guess I have some dosing to do. Thanks again for your continued assistance.