# My EI Calculations



## Ivydree (Jan 9, 2011)

Hey people!

This is it! I'm starting EI dosing in my newly installed tank! :cheer2::cheer2:

So, tank is a Juwel Rio 125 - with external filtration (say 120L net)

Chemicals are on their way, i ordered:

KNO3, KH2PO4, MgSO4 and trace mix

Trace mix is as follows: Fe 8.2% ; Mn 1.82% ; Zn 1.16% ; B 1.05% ; Cu 0.23% ; Mo 0.15%

So after using about 247 different calculations, I end up with this:

Fertilator gives me:

KNO3 - 6 grams
KH2PO4 - 0.3 grams
MgSO4 -5 grams

With this, I end up with 30.7ppm NO3 - 1.7ppm PO4 - 20ppm K - 4ppm Mg

Assuming this is concentration for a week, I wish to dose daily (easier for me)
I dose from Monday to Friday so 5 days a week, 4 weeks per month, that's 20 doses:
So, each dose, divided by five and multiplied by 20:

KNO3 - 24 grams
KH2PO4 - 1.2 grams
MgSO4 - 20 grams

I have a 500ml bottle with pump, so if I had the previous quantities to my bottle and dose 500/20 = 20ml per day from Monday to Friday I should end up with the correct amount.

Is this correct? Or am I mistaking somewhere?

Then, traces..... And here it's a bit tricky...

As I said, trace is as follows: Fe 8.2% ; Mn 1.82% ; Zn 1.16% ; B 1.05% ; Cu 0.23% ; Mo 0.15%

Is it then correct to say that if I add 1gram of trace mix, I add 1*8.2% = 0.082gram of Fe
Which, in my tank end up to be 0.082*1000/120 = 0.68ppm

Is this correct?

Moreover, are my concentrations correct? Which concentration should I aim for for traces?
Can I dose as follows: NPK every day (Monday to Friday) Traces on Saturday, Water Change on Sundays?
Is it a good idea to start dosing before the tank is cycled?


Lots of questions, I know, I'm wishing to do things the correct way... 


PS: Pardon my french, I'm actually french!


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## maboleth (Aug 13, 2013)

I cannot help you with everything but for traces, if I'm not mistaken, 8.2% means 82ppm in 1g of 1 litre solution. Dumping the whole bottle in 120l would add 0.683ppm of Fe in every 1l of aquarium water. That's very weak so I guess you'd have to add about 20g of traces in 1l water to reach optimal concentration.

If my calculations are right, if you mix 20g of traces in 1lit solution, you'll have to dose about 22ml to reach 0,3ppm Fe in 120l tank.


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## Zorfox (Jun 25, 2012)

Here is how I would mix my solutions. This is for 120L. Dosing is on alternating days as below.

Each dose is 20ML
In 500ml of water,

KNO3 add 15.653 G (3 teaspoons) one dose raises NO3 3.2ppm
KH2PO4 add 2.579 G (1/2 teaspoon) one dose raises PO4 0.60ppm
MGSO4.7H2O add 60.844 G (12 teaspoons) one dose raises Mg 2ppm or 0.46 dGH

Mon KNO3, KH2PO4, MGSO4
Tues Trace mix
Wed KNO3, KH2PO4, MGSO4
Thurs Traces
Fri KNO3, KH2PO4, MGSO4
Sat Traces
Sun 50% water change, don't ignore this!

As far as the trace, what are you using? The percentages are quite high for many things. Most are things that can become toxic such as zinc and copper. Below is an analysis of Plantex CSM + B. Even this can become a problem if we miss too many water changes. Compare this to what you are using.

Total magnesium----------------------------------1.5% 
Copper - chelated----------------------------------0.1% 
Iron - chelated-------------------------------------7.0% 
Manganese - chelated-----------------------------2.0% 
Molybdenum---------------------------------------0.06% 
Zinc - chelated------------------------------------ 0.40% 
Boron-----------------------------------------------0.04% 
EDTA - minimum content--------------------------55%

You can model those doses here. Try and keep the nutrients in these ranges.

EI target ranges
CO2 range 25-35 ppm
NO3 range 10-30 ppm
K+ range 10-30 ppm
PO4 range 1.0-2.0 ppm
Fe 0.2-0.5ppm or higher
GH range 1-2 degrees "extra" 17-40 ppm or higher

What is your current GH? It may be sufficient not to dose MGSO4. If it's very low you may need to add GH booster. Most water supplies are fine as far as GH (magnesium and calcium) though.

You may find it helpful to read this thread. I haven't posted it here yet but I may if some find it helpful. Get a cup of coffee first. It is a tad long but explains the basics.


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## maboleth (Aug 13, 2013)

Anyone knows what Cu dose is lethal for inverts? My trace mix has 13ppm Cu and 100ppm Zn in 1 litre of solution. I add 85ml each week to a 200 litre tank. However, my pH is 8.0, as far as I know, metals such as Cu are more deadly in softer waters.


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## Zapins (Jul 28, 2004)

0.37 ppm Cu is the LC50 value for cherry red shrimp. Meaning it is toxic at above that concentration.

The story of toxicity is not exactly straight forwards. Many other tank chemicals can make it less toxic, so 0.37 ppm isn't always the toxic mark.

The best relevant explanation of this and a list of other species and their copper toxicity ranges can be found here:
http://calc.petalphile.com/cu


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## maboleth (Aug 13, 2013)

Thanks for the page. So yeah, so many factors affect the Cu toxicity, it's not linear.

Each of my trace dose adds 0.0059ppm/l of Cu in tank. That's like 12x less than generic toxic level for Amano shrimp (0.072) that I also have.


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## Phil Edwards (Jan 22, 2004)

Ivydree,

The fertilator and original EI calculations are intended to tell you how much to add to your system at one time. If you're looking to make stock solutions to dose you'll need to do a couple things.

1. Determine the volume of your bottle.
2. Determine the volume of liquid dosed per pump. For example, ADA's pump bottles dispense 1mL per pump. 
3. Decide how many pumps you want to add to your system. 1, 2, 10?

If my dosing bottle is 500mL and the pump dispenses 1mL per pump and I want to dose 10 pumps per day then I would have to figure out how much chemical to add to 500mL so that the solution is concentrated enough to dose Xmg/L of chemical into my tank.

Let's use KNO3 as an example. KNO3 is 61% NO3 so every gram of KNO3 equals 610mg NO3 (assuming 100% purity) so 1.0 gram KNO3 in 500mL water equals 1220mg/L NO3 stock solution. 1mL of this solution equals 1.22 mg NO3. In order to supplement 30 mg NO3 per liter I would have to add 24.5mL solution to 1 liter. In my 227 liter aquarium, to get 30mg/L NO3 I would have to add 5563mL, 5.5 L of solution. YIKES!

Let's work on concentrating this solution. If 1 gram KNO3 = 1220 mg/L NO3 in 500mL then 100 grams KNO3 = 122,000 mg/L NO3 in 500 mL solution. 1mL of solution = 122 mg/L NO3. That will be 12.2 mg/L NO3 per 10L (approx 2.5 US gallons). 10 pumps will supplement a 100 liter aquarium by 12.2 mg/L NO3.

150 grams KNO3 = 18.3 mg/L NO3 per 10L, 200 grams KNO3 per 500mL (solution) = 24.4 mg/L NO3 per 10L per 1mL of solution added.

Keep in mind that the solubility of KNO3 is 316 g/L at 20 Celsius so you'll only be able to dissolve 158 grams of KNO3 into 500 mL at room temperature. Accounting for less than 100% purity (assuming 95% for food or pharmaceutical grade chemical) of your KNO3 then 158 grams will give you a solution of approximately 18 mg/L per 10L of aquarium volume per 1mL dosed. You'll also be dosing approx 12.3 mg/L K per 10L of aquarium volume.


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## OTPT (Sep 27, 2010)

> KNO3 - 6 grams
> KH2PO4 - 0.3 grams
> MgSO4 -5 grams
> 
> ...


Just one mistake, 500/20 = 25ml per day (not 20).



> As I said, trace is as follows: Fe 8.2% ; Mn 1.82% ; Zn 1.16% ; B 1.05% ; Cu 0.23% ; Mo 0.15%
> 
> Is it then correct to say that if I add 1gram of trace mix, I add 1*8.2% = 0.082gram of Fe
> Which, in my tank end up to be 0.082*1000/120 = 0.68ppm
> ...


Yes, that's correct.



> Can I dose as follows: NPK every day (Monday to Friday) Traces on Saturday, Water Change on Sundays?


I wouldn't do that. Because it means the whole week's worth 
of trace elements is dumped into the the tank at once 
and about half of it will be removed by the next day's water change.

And trace elements, especially chelated iron and manganese are prone 
to change into forms which is difficult or impossible for plants to use 
overtime in the tank water. Dividing it into smaller amount and dose 
more frequently is better.

You can look at this thread, he uses the same trace mix* and same tank 
size as you. He adds 0.6 grams 3x a week.
http://www.ukaps.org/forum/threads/...-the-end-juwel-rio-125.1152/page-8#post-20047

*I know because AE (aquaessentials.co.uk) was selling this trace mix 
by the time that journal was running.


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