just remember that being organic and sterile doesn't mean you can't overdo it, 400 w isn't going to make your plants grow fast enough to probably "justify" thatn need of nitrogen man, urine is best used for outdoor grows, and even then only as a corrective measure to combat a "hungry" plant.
typically only a high amount of light (1000 w or more HID, or REALLY efficient LED) will accelerate the photosynthesis to the point of nitrogen being deficient, a 400w probably not, but there are way more variables to that, container size, soil mix, cec, age, train methods, strain, etc.
in a perfect world you want long slow releases of nitrogen, grass clippings, neem meal, crab meal, etc.
dog hair is a good one if you have a furry friend that sheds, but only if you aren't giving them flea treatments and such. Those take a long ass time to break down.
another good one is feather meal, BUT only if you can source it from homesteaders/organic free range growers.
reason is the feather meal has scary amounts of arsenic present in almost ALL commercially available feather meals
which sucks cuz I really liked feather meals in my mixes yrs ago
but arsenic is arsenic...