Urine contains Urea which has the chemical formula of CO(NH2)2. It i the main source of ammonia from urine When it is oxidized it is converted CO2 and 2 ammonia molecules. It was first isolated from urine and is now manufactured in bulk for use as fertilizer and a chemical feedstock. Urea is also used in the Add Blue diesel emission control fluid.
https/en.wikipedia.org/wiki/Urea
Urea converts to ammonia rapidly due to heat or UV light. Some bacteria feed on it and some plants can apparently use it directly without waiting for it to be converted to ammonia. So in a fish tank urea should convert to ammonia rapidly. using raw urine instead may not be a good idea in a fish tank due to high levels of sodium chloride and potassium and hormones and pharmaceutical drugs. However pure manufactured urea is cheep and pure.
I have been experimenting with it. for a few weeks now. My tank was conically low on nitrogen and as a result I had high phosphate levels. Adding a potassium nitrate fertilizer did work but after the pants consumed it I was left with potassium rich water that would increase my PH. Urea doesn't have potassium so I purchased some. I couldn't find a dose recommendation so I just started small. I never did detect ammonia. It probably was there but at a low level I couldn't detect. No symptoms of ammonia poisoning ever appeared and my PH stayed stable. It looked good so I decided to stop let the tank reset to its nitrogen efficient state and try a different dose. My tank has not gone back to the nitrogen deficient state. Its now conically low on phosphates and possbly potassium. This means I no longer need to add nitrogen to keep my phosphates under control.
I curently have a jar of RO water with a small amount of urea added. I wanted to see how fast it converts to ammonia at room temperature without UV light. I also purchased a Hanna instruments Ammonia checker . Which has a resolution of 0.01ppm and and an accuracy of +/-0.05ppm of reading. This is what I have so far:
6/14 add 5 beads to water (it is in the form of small beads not a powder or liquid.I don't have any way to weigh this small amount accurately. Also I am not sure how muc water is in the jar. Its probably just under one quart.
6/16 0.06ppm
6/18 0.23ppm
6/20 0.38ppm
6/26 0.63ppm
7/1 0.92ppm
So it is generating ammonia although slowly.
Since I used pure RO water which doesn't have enough minerals to support bacteria growth. I would expect nitrite and nitrate would not appear. and in fact I have not detected any nitrate or nitrite. It is not cycling. However if you used water fertilized with a good plant fertilizer, like Seachem fluorish it should cycle. Possibly quite rapidly. If you also add bacteria from an an established tank. Note there is no ammonia smell from the jar and the water is still clear.
I purchased it from here:
http/www.loudwolf.com/store/ They sell a lot of the commonly used fertilizer ingredients as well as BROMOPHENOL BLUE (a ph sensitive chemical used in CO2 drop checkers) and Ammonia Chloride which can also be used to cycle a tank. most of what they sell is 99% pure and available in 4oz bottles at reasonable prices. most other place sell it by the pound which was way more than I needed.
the hanna ammonia mter I purchased
http/hannainst.com/products/checker-colorimeters/hi700-ammonia-lr.html