Nitrogen (N) from fish doo doo.
Phosphates (P) from decaying fish food.
Potassium's (K) only source is ferts.
I dont dose phosphates because my 30 gallon tank with about 25 inches of fish produces more than 2 ppm on its own (from the food).
I dont need to dose nitrates because of all the fish poo but i still do. I know lots of people dose ONLY K2SO4 and traces and have BEAUTIFUL tanks.
Hope that helps.
Loyal
Phosphates (P) from decaying fish food.
Potassium's (K) only source is ferts.
I dont dose phosphates because my 30 gallon tank with about 25 inches of fish produces more than 2 ppm on its own (from the food).
I dont need to dose nitrates because of all the fish poo but i still do. I know lots of people dose ONLY K2SO4 and traces and have BEAUTIFUL tanks.
Hope that helps.
Loyal