There isnt a definitive answer on whats the best way. There are many ways to do this and different people will give you different answers on whats best.
I use an aquarium specific ammonium chloride product as an ammonia source. There are a few brands. I use Dr Tims Ammonium Chloride.
A cocktail shrimp is often used. This will give a steady flow into the water, rather than a daily dose.
I would go with one of these methods.