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PHOS-OUT 4 Phosphate Remover

  • Enables controlled decrease of phosphate levels
  • Removes Phosphate
  • Removes Silicate
  • Removes Sulfid
  • Removes Tannins
  • Iron-Hydroxide based formulation

Saltwater & Freshwater
Controlled decrease
Removes waste materials
Clean water

Phos-Out 4 removes phosphate, silicate, heavy metals (e.g. copper) and tannic substances quickly, safely and permanently from the water and produces a sustainable improvement in water quality.

Phos-Out 4 specifically reduces phosphate levels in a way that is harmless for your animals and without affecting the pH value.

Phos-Out 4 promotes natural coral growth in the case of phosphate problems and effectively prevents the unwanted growth of algae, within a short time. 



  • Phosphate
  • Silicate
  • Heavy metals (e.g. copper) 
  • Coloured dissolved organic matter

Dosage incl. dosage calculator

Your aquarium
(net volume of water in litres)

Freshwater aquarium: 15 g per 100 L of water
Saltwater aquarium: 30 g per 100 L of water

Dosage in freshwater aquariums:
Use 25 ml (15 g) per 100 litres of water.

Dosage in saltwater aquariums:
Use 50 ml (30 g) per 100 litres of water.

Before application, thoroughly rinse Phos-Out 4 under water to remove dust.

Phos-Out 4 removes approx.:
Phosphate PO4                             49 – 70 g / kg
Silicate SiO2                                  10 – 12 g / kg
Heavy metals e. g. like copper        8 – 10 g / kg

FAQ Questions and answers

Note that bacteria necessarily need a certain amount of phosphate as an energy source in order to carry out important biological processes (such as denitrification NO3 nitrate –> N2 nitrogen) in the aquarium.

Since NO3PO4 Control increases the growth and performance of the bacteria in the aquarium, the phosphate requirement naturally increases too.

Therefore, measure the phosphate value regularly (at least once a day) and add Basic P if necessary.

In order to lower the phosphate value (PO4 value) in any saltwater or freshwater aquarium, there is the option of using MICROBE-LIFT Phos-Out 4 iron hydroxide granules or Phos-Out 4 liquid on a polymer basis. With Phos-Out 4 ganules you have a constant phosphate absorption over a longer period of time and with Phos-Out 4 liquid a fast, immediate reduction. Depending on the desired effect, you can choose between the two products.

Yes, phosphate (PO4) is an essential energy source for bacteria in every saltwater aquarium and in every freshwater aquarium. If bacteria have no or too little phosphate (PO4) available in the aquarium, they largely stop important biological processes such as nitrification (conversion of ammonium/ammonia into nitrite and then into nitrate) or denitrification (conversion of nitrate into nitrogen).

Since Phos-Out 4 granules also absorbs phosphate, silicate, heavy metals (e.g. copper) and yellow substances from the water in the aquarium, no general statement can be made here as to the time after which the granulate should be replaced. Here it is important to measure the substances to be absorbed and if the value does not fall further or rises again, the Phos-Out 4 should be changed. Depending on how much of the individual substances is present in the aquarium, this time varies from aquarium to aquarium.

Tips & Tricks
  • Start with the recommended quantity of Phos-Out 4 and increase it if phosphate levels remain high.
  • The ideal phosphate value in saltwater aquariums should be between 0.02 and 0.05 mg.
  • We recommend using Phos-Out 4 in a fluid bed filter or filter bag in a strong-flow area, such as exterior or internal filters.
  • Use our Substrate Cleaner regularly to remove phosphate deposits. During this application,
  • Phos-Out 4 has to be taken out of the aquarium cycle until the water is clear again.
  • Use Phos-Out 4 (iron hydroxide-based) alternating with Sili-Out 2 (aluminium-based), to avoid unwanted enrichment of aluminium or iron.

Can be optimally combined with

SILI-OUT 2 Silicate Remover


CARBOPURE Activated Carbon


ZEOPURE Zeolite coarse 5 – 9 mm


ZEOPURE Zeolite fine 1,5 - 3 mm