Korallen-Zucht Magnesium Complex – 500 ml

This Magnesium Complex from Korallen-Zucht supplies a key element for stony corals and calcareous algae, keeping levels in the optimal reef range.

Important element for stony corals and calcareous algae.

Recommended in any tank system. Optimum level of 1200 – 1280 mg/L.

Dosing: 3 ml per 1000 Liter / 250 gallons daily. Regular water tests recommended.

Compatibility

Marine reef aquariums. This is not a freshwater product.

Korallen-Zucht recommend magnesium supplementation in any reef system, and it matters most for stony corals and coralline algae — the two things in a reef tank that will not hold their own if magnesium drifts down.

The level to hold is 1,200 to 1,280 mg/l. That range is not arbitrary: magnesium is what keeps calcium and alkalinity in solution at reef levels, so a tank with low magnesium fights its calcium and alkalinity dosing and never quite holds either. Fix magnesium first, then the other two behave.

Dose 3 ml per 1,000 litres daily, and test regularly — Korallen-Zucht say so explicitly. Consumption varies enormously with how much stony coral and coralline you have, so the maintenance dose for one tank is wrong for another.

Freshness & Storage

Every batch we dispatch carries a minimum of 6 months' remaining shelf life. Store this product in a cool, dry place away from direct sunlight, with the cap or inner foil closed tightly after each use.

Backorder & Dispatch Timeline

This item is stocked to order. Back-orders are consolidated and placed with our overseas suppliers once a month, on the last day of the month, and all such orders are shipped before the 15th of the following month.

Back-orders cannot be cancelled once they have been placed with the supplier. If you cancel before that, payment-gateway charges of 2% plus GST are deducted and the balance refunded. In the rare case a supplier cannot fulfil the item, we will offer you an alternative first, and refund in full with no deduction if you would rather not take it.

Returns & Replacement

Returns are accepted within 7 days of delivery, provided the item is unused and in its original packaging. Manufacturer-sealed items cannot be returned once the seal is broken, and sale-priced items are not refundable.

If your item arrives defective or damaged, message us on WhatsApp with your order number — or email us, if you would rather — and we will replace it. Approved replacements are delivered within 3 to 5 business days. Transit damage is covered by insurance on every shipment. If tracking shows delivered but nothing reached you, tell us within 72 hours, which is the reporting window Indian couriers allow. Damage caused during installation or use is not covered; replacement spares for such cases are chargeable.

Full terms are on our Cancellation & Returns page.