Aquarium and pond equipment at the best prices!
For those passionate about aquariophily
Having trouble finalizing your order? Contact us 24 hours a day by email at information@zoanthus.fr.
Basin Analysis
5€ discount for your first order with the code: BIENVENUE05 (from 100€ purchase, offers cannot be combined)
Balling Products
Seawater supplements
Basic elements
Fresh Water Supplements
CO2 system
5€ discount for your first order with the code: BIENVENUE05 (from 100€ purchase, offers cannot be combined)
Water treatment
Bacterial Treatments
Adverse Treatments
Fish Care
Water treatment
Bacterial Treatments
Adverse Treatments
Fish Care
Water treatment
Bacterial Treatments
Fish Care
5€ discount for your first order with the code: BIENVENUE05 (from 100€ purchase, offers cannot be combined)
5€ discount for your first order with the code: BIENVENUE05 (from 100€ purchase, offers cannot be combined)
Sand
Substrate for reactor
Sea Salts
Pond Substrate
5€ discount for your first order with the code: BIENVENUE05 (from 100€ purchase, offers cannot be combined)
Seawater Equipment
Basin Equipment
5€ discount for your first order with the code: BIENVENUE05 (from 100€ purchase, offers cannot be combined)


Zoanthus Lab Phosphate 1000 ml is a concentrated solution designed to precisely correct phosphate (PO4³-) deficiencies in marine aquariums. Phosphorus is a key element in biological metabolism: it plays a role in coral growth, bacterial development, and the overall balance of the reef tank. Formulated with purified water and pharmaceutical- grade sodium dihydrogen phosphate dihydrate , this product guarantees a stable, perfectly measurable, and reproducible concentration. Free of chelators and unnecessary additives, it integrates perfectly into an ICP- based management system. A clear, controlled solution designed for discerning aquarists.
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Zoanthus Lab Phosphate 250 ml is a concentrated solution designed to precisely correct phosphate (PO4³-) deficiencies in marine aquariums. Phosphorus is a key element in biological metabolism: it plays a role in coral growth, bacterial development, and the overall balance of the reef tank. Formulated with purified water and pharmaceutical- grade sodium dihydrogen phosphate dihydrate , this product guarantees a stable, perfectly measurable, and reproducible concentration. Free of chelators and unnecessary additives, it integrates perfectly into an ICP- based management system. A clear, controlled solution designed for discerning aquarists.
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.

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.
The solution is formulated according to a precise protocol:
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.
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.

The essentials for reef aquariums
Complete analysis of the major elements and trace elements essential for the regular monitoring of your reef aquarium.
Ultra-comprehensive diagnosis
In-depth reading with expanded spectrum including fluoride, nitrates, KH and reverse osmosis water analysis.
Special reverse osmosis water
Precise control of your preparation water to ensure a perfectly healthy base before any remineralization.
The results of each analysis can be directly used in our free Zoa Aqua Manager calculator for precise and personalized dosing.

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.
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.
What they think about it
(and they are right...)
Laurent M.
Compliant (Translated review)