Results for “sand”

sand

Fine-grained silicate material commonly used as substrate. Often but not always chemically inert, and can therefore be used as a buffer.

Used in 846 profiles

deep sand bed

Method of filtration, mostly used in marine aquaria, whereby the increased depth of the sand substrate facilitates formation of an anaerobic layer where nitrate can be converted into nitrogen gas. Also known as "Jaubert" or "plenum" system and often associated with live sand.

silica sand

Sand containing a high concentration of silicon dioxide. Noted in aquaria for its purity, delicate appearance and lack of effect on water chemistry. Also known as silver sand.

coral sand

Sand originating from marine environments via bioerosion of the calcareous skeletal structures possessed by some organisms. Coral is not the chief constituent, however, with the majority of material deriving from foraminifera, calcareous algae, molluscs, and crustaceans.

Used in 6 profiles

live sand

Type of substrate mostly used in marine aquaria collected directly from natural marine habiats and packaged in such a way as to maintain the resident microorganisms. Significantly reduces the time required to mature a new aquarium.

parts per thousand

Unit expressing the part of a whole number in units of 1/1000. Abbreviated to ppt.

aragonite

Naturally-occurring, crsytalline form of calcium carbonate with a notable buffering capacity. Popular as a substrate or substrate additive in marine and freshwater aquaria where pH and hardness must be maintained at high levels, and has a more rapid, effective effect than coral sand, for example.

fluidised bed filter

Type of biological filter comprising a vertical column within which sand or other fine-grained filter medium is held in suspension, i.e., a fluidised state, by a continual upward flow of water. The many fine grains of filter media provide a huge surface area for bacterial colonisation.

riffle

Short, normally shallow stretch of fast-flowing, turbulent water in a stream; a small rapid; a rocky shoal or sandbar causing such a rapid.

Used in 105 profiles

brackish

Refers to water with a salinity between that of freshwater and seawater, technically 0.5 - 30 grams of salt per litre, equivalent to 0.5 - 30 parts per thousand (ppt).

Used in 114 profiles

cubic centimeter

A measurement of liquid, equivalent to a cube 1cm on each side (US spelling). Also known as a millilitre, since as it is one thousandth of a litre.

cubic centimetre

A measurement of liquid, equivalent to a cube 1cm on each side. Also known as a millilitre, since it is one thousandth of a litre.

microlitre

A measurement of liquid, equivalent to a cube 1mm on each side. One thousandth of a cubic centimetre/centimeter.

Rhodophyta

Division of eukaryotic algae containing thousands of species, most of which are multicellular and inhabit marine environments, e.g., many seaweeds.

Used in 3 profiles