# Flourish N, P and K are crazy!! (about seachem calculator)



## wiijixx (May 22, 2013)

I have Seachem fertilizers and I found a Seachem official website that calculates the dose.
It's crazy!
According to this calculator, to increase the nitrogen from 0 to 15 in my tank of 47.55 gallons i need.... 170 milliliters of flourish! and to raise the phosphate to 2, need 70 milliliters.
At these doses, the pot of 500 ml (which costs quite expensive) lasts only three weeks.
But the calculator on this website (fertilator) indicates a much lower amount.
Which of the two is correct? Its crazy.


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## wiijixx (May 22, 2013)

t's absurd, i just made my own calcs, based on 15000 ppm in flourish (official website) and seachen calculator is broken. Weird


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## OTPT (Sep 27, 2010)

Seachem's calculator results are pretty close. Totally useable.

Nitrogen.

Your 47.55 gallon tank is about 180 liters.

To get 15 PPM of nitrogen, you need 180x15 = 2700 milligrams of nitrogen. 
Then you (re)do the math, the result will be around 180 ml. for a 15000 PPM solution.

And that is "nitrogen", not "nitrate". The multiplier to convert nitrogen to nitrate 
is 4.427. In your case, divide the result by 4.427. Although the N in Seachem's Nitrogen 
is derived from both NH4 and NO3.


Phosphorus.

To reach 2 PPM of phosphate. Your tank needs 360 milligrams of phosphate.
This time it's easier, since the calculator unit is already phosphate, not phosphorus.
And both Seachem's and Fertilator suggest around 80 ml.....


Are they quite diluted? Yes. That's why dry ferts are popular.


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## wiijixx (May 22, 2013)

Thank you!!


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## binbin9 (Dec 22, 2011)

Most of what you are paying for is water then, and a label? =)


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## Diana K (Dec 20, 2007)

Exactly. And paying to have that water shipped to your local store.

Now that you have the container, buy JUST the active ingredient. You can make your own liquid fertilizers. You can also make them more concentrated so you can dose less and each bottle will last longer.

Here is one source of dry fertilizers. 
http://www.aquariumfertilizer.com/


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## 1.0reef (Apr 19, 2013)

Diana K said:


> Exactly. And paying to have that water shipped to your local store.
> 
> Now that you have the container, buy JUST the active ingredient. You can make your own liquid fertilizers. You can also make them more concentrated so you can dose less and each bottle will last longer.
> 
> ...


THANK YOU!
Perfect stuff to replace my nearly empty supply of Flourish


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## misant777 (Mar 21, 2014)

This 5Lb bag of Potassium Phosphate equates to something silly, like 504 liters of Seachem's Flourish Phosphorus.


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## foster (Mar 7, 2013)

I use Green leaf aquatic ferts, and mix my own. Much cheaper that way. And as previously posted, you can adjust strengths to you specific needs!!


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## Zapins (Jul 28, 2004)

misant777 said:


> This 5Lb bag of Potassium Phosphate equates to something silly, like 504 liters of Seachem's Flourish Phosphorus.


1 lb of potassium phosphate is roughly a 15 year supply for a medium sized tank high tech tank, so 5 lbs is essentially a life time supply.

SeaChem's fertilizers do have their uses. Low tech planted tanks do well with less nutrients.


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## Tugg (Jul 28, 2013)

But that is what Osmocote is for. In a low tech you just recharge your MTS with some DIY root tabs


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