Urea as nitrogen

[RyanScanner]

Just wondering if anyone has used urea as nitrogen source. If so how did they prepare the solution. I have 25kg bag I wanted to start preparing a solution, apparently I should match with a trace element solution with nickel in it. Mainly I just want to know how much pure Urea to water I should mix. Or if it matters Irr not.
I was thinking 1:1 and add to doser aiming for 10ppm at first nitrogen.

 

[Milingu]

Urea consits to 54% of nitrogen if I remeber correctly. Using urea is one way to start a cycle in your tank.
But I would not use it in a tank with fish because the bacteria will process the urea -> ammonium -> nitrite -> nitrate. You will have a high load of ammonium/ammonia and nitrite in your tank and in addition you can only measure the nitrogen with a delay.