Seachem Flourite Dark 3.5kg

Seachem Flourite is a stable, porous clay gravel substrate that supports healthy root growth in the natural planted aquarium for its entire life.

• Premium natural gravel for the planted aquarium.
• Good for the life of the aquarium.

Seachem Flourite Dark is a specially fracted stable porous clay gravel for the natural planted aquarium. Its appearance is best suited to planted aquaria, but may be used in any freshwater aquarium environment. Flourite Dark is most effective when used alone as an integral substrate bed, but it may be mixed with other gravels. Gravel modifiers such as laterite are not necessary. Flourite Dark is not chemically coated or treated and will not alter the pH of the water. Flourite Dark is good for the life of the aquarium and need not be replaced.

The Seachem Flourite Dark 3.5kg forms the base layer of a planted tank — see our guide to Substrate & Aquasoil for how to pick and layer substrate for healthy root growth.

Specifications

Seachem item #3733 (3.5 kg). A specially fracted, stable, porous clay gravel for the planted aquarium, in the dark colourway. Not chemically coated or treated, and it will not alter the pH of the water.

It is good for the life of the aquarium. Seachem's own claim: it is never exhausted and never needs replacing. That is the difference between a clay gravel like this and a nutrient-charged aquasoil, which is spent after a couple of years.

No gravel modifier is required. Laterite and the rest are unnecessary underneath it.

It may be used in any freshwater aquarium, though its appearance is aimed at planted tanks. It can be mixed with other gravels, but Seachem consider it most effective used alone as the whole bed.

Seachem make Flourite Dark in 3.5 kg and 7 kg bags.

Setup & Use

Rinse it first. It is pre-washed, but it is a natural product and it picks up dust in transit. Some fines will remain however long you rinse. That is normal and costs the tank nothing beyond a week of cleaning the filter more often than usual.

Fill the tank through a bowl. Stand a bowl on the substrate and pour into the bowl so the water overflows softly onto the bed rather than cratering it. Initial cloudiness is normal and clears with mechanical filtration over a day or two; Clarity accelerates it.

Use it as the substrate, not as a thin layer under something else. It works as the whole bed; a 2 cm capping layer of gravel over it defeats the porosity that makes it worth buying.

Expect to clean the filter more often for the first week or so while the remaining fines settle out. After that it behaves like any inert gravel.

Coverage: Seachem's own project calculator turns tank dimensions and intended substrate depth into a count of 3.5 kg or 7 kg bags. Use it before ordering.

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.