I am not familiar with the Profito product, but from what I have seen on their website Profito 500ml - EasyLife - Liquid Fertiliser - Fertilisers
I would expect it is a decent complete liquid fertilizer for aquarium plants, similar to Seachem's Flourish Comprehensive Supplement.
As for the Flourish Nitrogen, I would not recommend this. For one, this product is intended to be used in conjunction with their other macro-nutrients--Flourish Excel, Flourish Potassium, Flourish Iron--and Flourish Trace. Flourish Comprehensive Supplement ties these together. This is a lot of fertilization and not necessary in the average planted tank.
But more to the point on the Nitrogen, aquatic plants prefer to take up nitrogen as ammonium, and this occurs in an aquarium in the form of ammonia which is continually being produced by fish and bacteria, and from the breakdown of organics. In most fish tanks, there will be more than sufficient ammonia/ammonium to provide all the nitrogen that plants require. Adding it is only going to raise the balance for everything else, unnecessarily.
I will tie this together a bit more in my response in your other thread.
And before I forget, welcome to Tropical Fish Keeping forum.