Phosphate Supplement Fertilizer

Some intensively planted and lighted pools with a moderate till low fish population need, in comparison to the majority of typical aquariums, a supplement to the basic food stuff phosphorus - P resp. phosphate - PO₄.

Ingredients

Contains potassium hydrogen phosphate (KH₂PO₄)

Dosage

Adding 1 ml to 50 l tank water increases the phosphate ratio by 0.1 mg/l

The desired value ranges between 0.1 - 0.2 mg/l phosphate. More than that is seldom necessary and usually only promotes algae growth unnecessarily.
(Simultaneously the applied salt increases the potassium ratio by insignificant 0.04 mg/l

Phosphate can also be used as an start-up fertilizer. Add until ~ 0.25 mg/l are reached and only add fertilizer again, after the level has been on zero for a while.
Water plants can store phosphate very well. Therefore, this method is useful for getting rid of algae, as they are not able to store much phosphate due to their smaller size.