• Premium natural substrate for the planted aquarium
  • Good for the life of the aquarium
  • Rinse right in the bag (3.5 kg only)


Flourite® 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® 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® is not chemically coated or treated and will not alter the pH of the water. Flourite® is good for the life of the aquarium and need not be replaced.

“The folks at Seachem have done a wonderful job responding to the needs of aquatic gardeners. Seachem has developed a complete line of well-researched products for the planted aquarium. My personal favorite is Seachem Flourite®. In my opinion this is the best product available as a substrate in the planted aquarium. It is easy to use, attractive, and the plants love it. Since setting up my first Flourite tank, I have used nothing but!”

Karen Randall Editor of The Aquatic Gardener

To determine the number of bags required for your aquarium, please note that each bag (7 kg, 15.4 lbs) occupies a volume of approximately 7,000 cm3 (425 cu. in.). To determine your desired volume multiply tank width by length by desired depth. This bag is sufficient for about a 5 cm (2 inch) deep bed in a typical 40 L (10 gallon) tank.


Although it is pre-washed, because Flourite® is a natural product, it may become dusty in transit and require rinsing before use to remove any residual dust.

NOTE: The specialized mesh bottom of the 3.5 kg size allows it to be rinsed right in the bag.

TIPS: When adding water to aquarium, fill slowly to avoid disturbing Flourite® substrate bed. Place a bowl in the aquarium and add water directly to the bowl, allowing water to overflow softly on to the gravel bed. Initial cloudiness is normal. To remove cloudiness, use mechanical filtration (such as filter floss). Clarity™ clearing.


3.5 kg, 7 kg

Wondering how many bags you will need for your project? It's easy to figure out with this gravel calculator. Just enter the length and width of your aquarium along with the desired depth of the substrate and click calculate. Note: The calculator will always round up. For example, you can't purchase 1.3 bags, so it will return 2 bags.

If you plan on varying the depth of your substrate, use an average depth as your desired substrate depth.

You require:

7 kg bag(s) or 3.5 kg bag(s)

A: Depending on how dense the growth or how dense you wish it to be, the use of Flourish,(foliar feeding), Flourish Tabs (root feeding) and Flourish Iron can be useful and helpful, but are not necessities.

A: Flourite will work fine with an UGF. Flourite will not soften or decompose to an unsuitable state. In addition, Flourite has an attractive, natural appearance.

A: We are currently investigating this claim and will make our findings public when we have all the facts. However, all iron containing substrates (even laterite) contain around 5 ppm of arsenic (as insoluble ores (aresenopyrite or orpiment)). The keyword here is "insoluble" because if either of these ores were in any way soluble the water would contain far beyond the 0.05 - 12 ppm toxicity that plants show toward arsenic. The fact that thousands of people use this product in their planted tanks without a single incident of plant death (on the contrary, all we hear are stories of fantastic growth!), is a strong indicator that no arsenic is being leached.

A: It is possible to experience an excess of particles/dust from this product due to frictional action in packaging and shipping. Flourite Red is an ore with a rich mineral composition and is not chemically coated. Even though some small particles washed away, the product is completely viable and will still offer the same benefit. A better way to add this to an established aquarium is to add small amounts at a time a half day to 24 hours apart making sure these small amounts are rinsed thoroughly. You can also use a water clarifier like our Clarity to clump any small free floating particles together making it easier for your mechanical filter to catch. Your cartridges/floss will tend to clog from all the particles being trapped and will need rinsing or replacing regularly.

A: No, Flourite will not break down under long term aquarium use.

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0493 Flourite 3.5 kg
0495 Flourite 7 kg