Specialised Fertiliser is added each week when the water is changed. The pump bottle dispenses 1,2 mL per push.
We recommend 6 mL (5 pumps) per 50 L water weekly. However, we recommended that this is set in accordance with plant requirements. Specialised Fertiliser contains, in addition to micro-nutrients, all essential macro-nutrients. The fertiliser is particularly suitable where plants display a lack of nutrition. However note that if algae growth starts, Specialised Fertilser will promote this growth.
Specialised Fertiliser contains nitrogen (N) and phosphorus (P). Dosage must therefore be adapted to plant absorption rates, to avoid undesirable algae growth. Where signs of algae growth develop, reduce the dosage by 50% and increase water changing frequency by 50%. Changing the water not only reduces the concentration of nutrients in the water, but also removes algae spores, remnants and other accumulated elements from the aquarium water.
I have a heavily planted tank and was using different fert combinations from Seachem. Tropica specialized nutrition is really good. Two pumps on alternate days for my 20 gallon tank. That's all :) Now I am forced to trim my plants on a weekly basis. This would save your money for sure.