help with theplantedtank's EI article and dosing calculator

[jarthel]

I was reading theplantedtank's EI article and it mentions a solution of 33grams of KNO3 for 250 distilled water. The dosing recommendation is to use 5mL of the solution per 50L of water. so if my tank is 300L, I need to put in 30mL (5mL x (300/50)) of the solution.

My confusion lies in the ppm that is put into the tank.

e.g.
using the dosing calculator on the same website, 33grams of KNO3 dissolved in 250mL of water equates to around 1.6ppm of nitrate per 1mL of the solution in a 50L tank. Since I need 30mL, 30mL x 1.62ppm/1mL = 48.6ppm in 1 dosing. And it seems I need to dose thrice a week so that'll be around 140ppm of nitrate/week.

According this article (http://www.ukaps.org/EI.htm), I only need 20ppm of nitrate per week.

maybe I'm misunderstanding how EI works?

thank you very much for the help

 

[chump54]

are you sure you didn't select teaspoons rather than grams in the 'amount to add' radio buttons?

other than that I think your maths/understanding is right.

I would say that with a large tank you might be better off dosing dry salts. I find it easier to adjust. say for example your blyxa japonica is going a bit red (a sign of possible N deficiency) it's easy to up the dose by a 1/4 teaspoon or 1/2 teaspoon or 1 teaspoon or what ever.

Chris

 

[JamesC]

I think your maths has gone wrong. 33g dissolved in 250ml water to make the solution. If you dose 5ml in 50 litres of water you add 8ppm NO3. Do this 3 times a week and you add 24ppm NO3.

So if your tank is 300 litre then you need to add 300/50 = 6 times the amount ie, 30ml 3x a week to achieve the same dosing rate.

James

 

[jarthel]

okay. I got a better understanding now after reading James' reply.

thanks everyone