ZOANTHUS LAB - Phosphate Plus - 250ml

The role of phosphorus in reef aquariums

Phosphorus, measured as phosphates (PO4³-) , is an element naturally present in seawater at very low concentrations. It plays a fundamental role in biological processes: energy synthesis (ATP), cellular metabolism, bacterial development, and coral tissue growth.

In a modern reef aquarium, protein skimming, resin adsorption, biological consumption, and certain filtration methods can lead to an excessive drop in phosphate levels. Too low a level can limit coral growth and disrupt bacterial dynamics. Maintaining a controlled level helps preserve a stable nutrient balance , especially in tanks with high biological demands.

We offer a full range of products to target the main elements of seawater following ICP analysis or manual testing.

A simple, direct and controlled formulation

Zoanthus Lab Phosphate solution is prepared from sodium dihydrogen phosphate dihydrate ( _NaH₂PO₄ · _{2H₂O )} dissolved in purified water (RO/DI). The raw material used is pharmaceutical grade , guaranteeing purity, consistency, and traceability.

No chelating or complexing agents are added. At this concentration, phosphate is naturally soluble and stable in its inorganic form. This choice ensures accurate ICP readings and avoids any interference from organic or complexed forms.

• ✔ Stable inorganic solution
• ✔ Chelator-free
• ✔ Compatible with Balling, Triton method and other reef methods
• ✔ Consistent and reproducible ICP results

Concentration and dosage

The solution is formulated according to a precise protocol:

• Concentration: 10 mg/mL PO4³-
• Recommended dosage: 1 ml per 100 L of water
• Effect: +0.1 mg/L of phosphates (PO4³-)
• Correction limit: do not increase phosphates by more than 0.02 mg/L per day.

Supplementation should always be based on a recent ICP analysis or a reliable test. In cases of significant deficiency, dividing the correction over several days helps avoid any sudden changes that could impact biological stability.

Zoa Aqua Manager: your smart dosing assistant

Each Zoanthus Lab product can be controlled via our free Zoa Aqua Manager calculator. In just a few seconds, you get a precise and personalized dosage from your ICP analysis (Zoanthus Labs or any other laboratory).

No more manual calculations: enter your water volume, your measured value and your objective, and the system automatically calculates the appropriate correction, with the possibility of progressive dosing for optimal stability.

A tool designed by aquarists, for demanding aquarists.

Three ICP analyses tailored to each need

ICP REEF

The essentials for reef aquariums

Complete analysis of the major elements and trace elements essential for the regular monitoring of your reef aquarium.

• Key parameter tracking
• Detection of deviations
• Over 40 parameters analyzed

ICP MAX

Ultra-comprehensive diagnosis

In-depth reading with expanded spectrum including fluoride, nitrates, KH and reverse osmosis water analysis.

• Most detailed analysis
• Over 45 parameters analyzed + reverse osmosis water
• For discerning aquarists

ICP PURA

Special reverse osmosis water

Precise control of your preparation water to ensure a perfectly healthy base before any remineralization.

• RO/DI water verification
• Contaminant detection
• Secure the preparation

The results of each analysis can be directly used in our free Zoa Aqua Manager calculator for precise and personalized dosing.

Usage and storage instructions

Add to a well-circulated area of the aquarium or to the sump. Shake well before use.

Store away from light, between 15 and 25°C. Recommended shelf life: 12 months after manufacture.

• Product intended exclusively for use in aquariums!
• Keep out of reach of children! Do not swallow! Do not ingest.
• Not suitable for animal feed.
• In case of contact with skin or eyes, rinse thoroughly with water.

As with any trace element, excessive supplementation is unnecessary and can unbalance the water. Regular monitoring via ICP analysis remains the most reliable method for maintaining a stable aquarium in the long term.