Inert sand

Also known as: Pool filter sand, Silica sand, Play sand (washed), Black diamond blasting sand

Properties

pH effect	neutral / inert
KH (carbonate hardness)	neutral
GH (general hardness)	neutral
Nutrient load	none
Ammonia release initially	No
Particle size	0.2 to 0.8 mm
Longevity	indefinite
Cost tier	low

How it affects the tank

Provides no nutrients to root feeders, so heavy-feeding plants (swords, crypts) yellow and stall without root tabs
Corydoras catfish, kuhli loaches and other substrate-sifters do well on fine sand, which lets them forage and sift without risking their barbels on sharp grit
Uniform fine sand can develop anaerobic pockets over time; gentle periodic stirring or Malaysian trumpet snails prevent hydrogen sulfide buildup
Easy to clean by holding a gravel vacuum just above the surface, so debris lifts off without pulling up the sand

Care notes

Rinse it aggressively before adding it to the tank, or expect cloudy water for hours. Pool filter sand is the cheapest reliable option in the US, and 'black diamond' sandblasting sand is industrial grade but works in freshwater after thorough rinsing. Wash play sand especially well to remove fine silt and dust before use. Most of these are silica (quartz) sand, which is chemically inert.

Plants that work in inert sand

61 aquarium plants in the catalog list this substrate as compatible.

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Properties

How it affects the tank

Care notes

Plants that work in inert sand

Further reading