Results for “GH”

symbiosis

Close, long-term association between two different biological species. Often obligatory and often, though not always, with a mutual benefit for both organisms.

Used in 2 profiles

tendon

Band of tough, fibrous, inelastic connective tissue that connects a muscle to a bone. Primarily composed of collagen.

Used in 3 profiles

total dissolved solids

Measure of the total concentration of both organic and inorganic, microscopic particles suspended in a given liquid. Usually applied only to freshwater systems and measured using a conductivity or total dissolved solids meter with results expressed in units of mg per unit volume of water (e.g., mg/L) or parts per million (ppm). Soft water with low pH generally has low levels of total dissolved solids whereas harder water with higher pH tends to contain correspondingly increased concentrations. Often abbreviated to TDS.

Used in 2 profiles

total length

Straight line measurement of specimen's length taken from the tip of the snout to the tip of the longer lobe of the caudal fin, if applicable, and not taking the curve of the body into account. If the caudal lobes are of equal length they may be compressed along the midline before the measurement is taken. Abbreviated to TL.

Used in 6 profiles

translucent

Allowing light but not detailed images to pass through; semitransparent.

Used in 13 profiles

transparent

Allowing light to pass through and clear enough that detailed images can be seen.

Used in 69 profiles

trickle tower

Large filter particularly suitable for outdoor ponds and large aquaria, consisting of a series of vertically-arranged chambers filled with one or more types of media. Water is pumped to the top chamber where it is dispersed, most often using a spray bar. It then percolates down through the other chambers via gravity before being returned to the pond or aquarium.

type

Can be used to refer to any taxonomic group, the characteristics of which are used for defining related, higher or lower ranking groups. For example, the type of a nominal species is a specimen (type specimen), the type of a nominal genus is the nominal species (type species), and the type of a nominal family is the nominal genus (type genus).

Used in 783 profiles

ultraviolet

Invisible, continuous spectrum of light having a wavelength just shorter than the violet end of the visible spectrum but longer than that of x-rays.

ultraviolet steriliser

Used to kill bacteria in the water column by exposing it to ultraviolet light.

undergravel filter

A filter which works by drawing water down through the substrate, where the cycle bacteria colonies are located, before returning it to the aquarium. Difficult to keep clean and now considered old fashioned.

uninomen

Scentific name comprising a single word, used for taxa higher than genus.

ventral-fin

Either of the pair of fins, also known as pelvic fins, attached to the pelvic girdle in fishes that help control the direction of movement. Correspond to the hind legs in higher vertebrates and vary in position depending on taxon. Sometimes absent entirely.

Used in 74 profiles

watercourse

A natural or artificial channel through which water flows; a stream or river.

Used in 1 profile

wet/dry filter

Type of filter normally placed under the aquarium, and often home-made. The basic premise is that water trickles vertically downards through separated compartments containing mechanical and biological filter media with spaces inbetween so that it is also exposed to the air briefly. It then collects in a base chamber or sump from where it is pumped back to the main aquarium. There are many commercial designs available, some of which are more effective than others. Not popular in marine reef aquaria due to the associated accumulation of nitrates as by-product.

wild-collected

In reference to aquarium fishes, caught in the natural habitat; not bred in captivity.

Used in 10 profiles