• Natural oolitic aragonite for all types of marine, reef, and tropical aquaria.
• Assists in stabilizing calcium and alkalinity.
• Helps prevent large pH declines.

Seachem Meridian is an all natural oolitic (spherical or egg shaped) aragonite substrate for all reef and marine aquaria. Seachem Meridian is the premium aragonite substrate for the reef aquaria. It’s grain size (a fairly uniform 0.25 – 0.50 mm) is ideally suited to reef inhabitants and it’s chemical composition will assist in stabilizing calcium and alkalinity while preventing large pH declines. Unlike competing “wet” products marketed under the guise of being “live”, Meridian is sold dry, thus you pay only for gravel and not for unneeded water. These products imply that they contain living, microscopic animals when in fact they only contain common bacteria. Dry or wet, there are bacteria on every substrate available. If one is concerned with shortening the aquarium cycle time for a new system, then the use of a product designed for that particular purpose would be more appropriate (such as Seachem’s Stability).

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.

Filter media and substrates carry no manufacturing or expiry date — their working life begins on first contact with water, not on the shelf.

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.