Ichthyological terms, not general ones.
Purification process, often abbrevaited to DI, by which mineral ions are removed from water, usually via ion exchange over a specialised type of resin. The process does not remove non-ionic molecules thus organic cells such as bacteria tend to remain. Often used in conjunction with reverse osmosis to produce more-or-less pure water which normally requires a degree of remineralisation before being used in aquaria.
Device used to purify water via the process of deionisation. Some units combine both reverse osomosis and deionisation functions.
Vertically or dorsoventrally flattened.
Used in 51 profiles
Innermost layer of skin containing nerve endings and blood vessels. Lies under the epidermis and also known as corium.
In icthyology, the nomenclatural act by which the type specimen of a previously or newly-established genus, subgenus, species, or subspecies is fixed via an express statement.
Used in 6 profiles
In biology, organic debris most often formed via the decomposition of organisms.
Used in 205 profiles
Differing from one another; exhibiting variety.
Used in 143 profiles
Positioned or orientated between the dorsal and ventral surfaces.
Used in 3 profiles
A membrane, paired, bone in the upper jaw, located ventrally on the skull. Some fishes, such as serrasalmids, possess small tooth-like projections known as ectopterygoid teeth on this bone.
Used in 4 profiles
Used in reference to a closed drainage basins with no outflow to other bodies of water, the bottom of which often contains a salt lake or salt pan. Water leaves only via evaporation or seepage.
Used in 7 profiles
Arising from or located on a neural arch of a vertebra.
A fish egg within which the embryo has developed to a point whereby the eyes are visible through the external membrane.
Capable of functioning or existing under varying environmental conditions.
Used in 96 profiles
Process of moving water over eggs or fry via rapid movement of the fins, thus aerating or removing solid particles from them.
Used in 42 profiles
Producing or capable of producing offspring or vegetation. Sometimes used in reference to particularly productive organisms.
Used in 33 profiles
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.
Chemical process whereby hydrophobic molecules are removed from a liquid via rising columns of foam, e.g., the process of organic-waste removal taking place within a protein skimmer.
Fish food preserved by rapid freezing and drying in a vacuum.
Gas-filled sac with 1-3 chambers, situated just below the vertebral column in most ray-finned fishes. Its primary function is to aid in buoyancy by offsetting the weight of heavier structures such as bone, but is also used for respiration or sound production in some species. Often reduced in benthic fishes and sometimes absent altogether. Also known as the air or swim bladder.
Used in 104 profiles
Measure of the overall concentration of calcium, magnesium and other ions in a water sample with values usually quoted in units of degrees (dGH), of which 1 dGH corresponds to 17.848 ppm. Also referred to as total or permanent hardness.
Used in 59 profiles