Seachem Black Flourite Sand (7 kg)
Flourite® Black Sand is a specially fractured, stable, porous clay gravel designed for natural planted aquariums. Its dark appearance complements planted environments well and is suitable for use in any freshwater aquarium. The sand is most effective when used as a standalone substrate, though it can be mixed with other gravels. No gravel modifiers like laterite are required.
Flourite® Black Sand is not chemically coated or treated and does not alter water pH. It is durable and long-lasting, designed to support the life of the aquarium without needing replacement.
| Specification | Value |
|---|---|
| Weight | 7 kg (15.4 lbs) |
| Volume | Approximately 5,500 cm³ (320 cu. in.) |
| Material | Clay gravel |
| Use | Planted aquariums, freshwater environments |
| Chemical Treatment | None |
| PH Impact | None |
FAQ
Can I mix Black Flourite Sand with other types of gravel?
Yes, Black Flourite Sand can be mixed with other gravels, though it performs best when used alone as a substrate.
Does this sand affect the pH of the water?
No, Black Flourite Sand is not chemically treated and does not alter the pH of the water.
How much sand is needed for a specific aquarium size?
Each 7 kg bag occupies approximately 5,500 cm³ (320 cu. in.). Multiply your desired substrate volume by the bag size to determine the number of bags required.

Sebastian Paige –
I’ve used this sand in my planted tank for over a year. The roots grow well, and the fish seem to be thriving. It doesn’t change the water chemistry, which is a big plus. The color is consistent and looks natural in the tank.
Owen Reid –
The sand is easy to work with and holds nutrients well. I didn’t need to add any substrate enhancers. My plants have grown steadily since switching to this sand.
Megan Carr –
Great product for a planted aquarium. It’s stable, doesn’t shift easily, and the dark color adds depth to the tank. No pH changes observed after several months of use.