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Anyone good with calculations for Seachem?

980 Views 4 Replies 4 Participants Last post by  Chris_Produces
I'm trying to figure out the amount of Seachem N and P. Currently reading 0 for both in the tank. I noticed my growth came to almost a halt in two days.

Using the formula on the back .05*vn=m (using .05 due to reading a nitrate increase)

v=volume of tank in gallons

n=desired nitrogen increase in nitrates (using .05 instead of .25 per instructions on bottle)

m=volume of seachem in mL

Plug in my values to get my nitrates to 10ppm---- .05*40*10=m

I get 20mL...That sound right to everyone else? I've used the YANC and it says to use 22mL. I want to make sure that 10ppm is about normal to shoot for to the other people dosing on a regular basis in a high light, Pressurized Co2 tank. That seems to be a pretty general consensus.
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http://www.fishfriend.com/fertfriend.html
I do Tetra Pride and Flourish Comprehensive only in liquid, but that link may
help you get an answer. I've never used it so really can't say, just bookmarked
it when I saw it.
I'm trying to figure out the amount of Seachem N and P. Currently reading 0 for both in the tank. I noticed my growth came to almost a halt in two days.

Using the formula on the back .05*vn=m (using .05 due to reading a nitrate increase)

v=volume of tank in gallons

n=desired nitrogen increase in nitrates (using .05 instead of .25 per instructions on bottle)

m=volume of seachem in mL

Plug in my values to get my nitrates to 10ppm---- .05*40*10=m

I get 20mL...That sound right to everyone else? I've used the YANC and it says to use 22mL. I want to make sure that 10ppm is about normal to shoot for to the other people dosing on a regular basis in a high light, Pressurized Co2 tank. That seems to be a pretty general consensus.
Hi Chris_Produces,

I like to do things the easy way; here is a calculator that has Flourish Nitrogen, Phosphorus, Potassium, Iron, and Calcium / Magnesium (Equilibrium) along with target levels. Be sure to input gallons at top of calculator.
The EI dose for nitrogen is actually 7.5ppm per dose. Dosed 3 times per week. The calculations below are based on that. You can change them for 10ppm if you like. The results from YANC are closer than your formula.

Here is a good explanation of the math behind the calculations.

The formula is,

Desired ppm / % of element in fertilizer x 75 (75 is the constant for ounces per gallon)

SO....

7.5 ppm / 1.5% (nitrogen) x 75 = 0.0666 ounces per gallon

0.0666 x 40 (gallons) = 2.664 ounces

Convert ounces to milliliters,

2.664 * 29.57 = 78.77448 ml

Since we want 7.5 ppm of nitrate NOT nitrogen we convert that dose to nitrate. The reason for this conversion is that nitrate molecule weighs 62 grams per mole; the nitrogen content of nitrate is 22.5% of the total weight of the molecule. So we convert it like this...

78.77448 * 0.225 = 17.724258 ml

So the dose is roughly 17.7 ml to raise NO3 levels to 7.5ppm in 40 gallons.

So that said you can do the math yourself or use the YANC. Calculators are easier. Yet that is the math behind the curtain lol.
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The EI dose for nitrogen is actually 7.5ppm per dose. Dosed 3 times per week. The calculations below are based on that. You can change them for 10ppm if you like. The results from YANC are closer than your formula.

Here is a good explanation of the math behind the calculations.

The formula is,

Desired ppm / % of element in fertilizer x 75 (75 is the constant for ounces per gallon)

SO....

7.5 ppm / 1.5% (nitrogen) x 75 = 0.0666 ounces per gallon

0.0666 x 40 (gallons) = 2.664 ounces

Convert ounces to milliliters,

2.664 * 29.57 = 78.77448 ml

Since we want 7.5 ppm of nitrate NOT nitrogen we convert that dose to nitrate. The reason for this conversion is that nitrate molecule weighs 62 grams per mole; the nitrogen content of nitrate is 22.5% of the total weight of the molecule. So we convert it like this...

78.77448 * 0.225 = 17.724258 ml

So the dose is roughly 17.7 ml to raise NO3 levels to 7.5ppm in 40 gallons.

So that said you can do the math yourself or use the YANC. Calculators are easier. Yet that is the math behind the curtain lol.
That's cool. It's nice to know where all these calculations come from. This has helped a lot. Thanks.
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