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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 Iron 250 ml is a concentrated solution designed to precisely correct iron deficiencies in marine aquariums. Present in trace amounts in seawater, iron (Fe) plays a key role in numerous biological processes, particularly for beneficial microalgae, certain bacteria, and the overall balance of the reef. Formulated with purified water , a stabilizer, and pharmaceutical-grade iron(II) sulfate heptahydrate , this supplement guarantees a stable, clear, and perfectly measurable concentration. Free of complex chelating agents, it integrates ideally into a rigorous management system based on ICP analysis. A precise solution, designed for discerning aquarists.
Iron is an essential trace element present in trace amounts, generally expressed in µg/L. In reef aquariums, it is often monitored via ICP analysis because it can be consumed quickly and vary depending on skimming, export, filtration and the density of life in the tank.
Properly maintained iron levels contribute to the proper functioning of the microfauna and certain biological pathways. The goal is to correct deficiencies only when they are confirmed , and then stabilize them through gradual and controlled supplementation.
We offer a full range of products to target the main elements of seawater following ICP analysis or manual testing.

The Zoanthus Lab – Iron solution is prepared from iron(II) sulfate heptahydrate ( FeSO4 · 7H2O ) , dissolved in purified water (RO/DI), with the addition of a stabilizer.
Iron(II) can oxidize naturally over time. To improve stability, the formulation includes a stabilizer (sodium citrate dihydrate) . The raw material used is pharmaceutical grade to ensure a clean, stable, and reproducible composition.
The solution is formulated according to a precise protocol:
Supplementation should always be based on a recent ICP analysis . Regular monitoring allows for precise adjustments, avoiding overdosing, while maintaining a stable tank in the long term.
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...)
Virgilio d.
Excellent (Translated review)
Yoan F.
Impeccable (Translated review)
Laurent M.
Compliant (Translated review)
Francois-Xavier R.
1st use (Translated review)