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Q10446 - INFO: Saltwater, Freshwater and Pond Glossary – June 2007
Acclimation - the process in which the water an organism comes in is balanced to the water in the display tank the orgainism will be going into.
Acidic – measuring below neutral pH (1.0-6.9)
Acrosphere-  The swelling at the tip of a tentacle that is full of nematocysts.
Aerobic-  pertains to requiring the presence of oxygen to live
Aerobic bacteria – bacteria that require oxygen to survive
Ahermatypic-  Pertains to corals that do not have zooxanthellae.  Generally non-reef building.
Algae-  Simple rootless plants that grow in bodies of water in relative proportion to the amount of nutrients available.  Algae produce oxygen (photosynthsize) with sunlight (natural or artificial) and use oxygen (respire) during the night hours.  Some types are benefical to aquatic environments while others can be nuisances
Alkaline – measuring above neutral pH (7.1-14.0)
Alkalinity - The capacity of a system to resist a downward change in pH; also know as carbonate hardness
Ammonia – a compound of Nitrogen and Hydrogen, formed in the anaerobic decomposition of organic matter.   Ammonia can also be added to public water sources to bond with chlorine to form chloramines.
Allopathy - the stunting of growth or inhibition of growth of aquatic animals by means of chemical warfare by another competing animal of the same or different species.
Anaerobic bacteria – bacteria that survive in conditions void of oxygen. 
Aquascaping - The arranging or decorating of an aquarium with ornaments and rocks such as plants (live or plastic), driftwood, ceramic decorations and rocks.
Aragonite- A calcium based sand or substrate used in saltwater aquariums.
Artemia-  Also known as brine shrimp.  They are small crustaceans that live in salty water.  Artemia nauplii, or baby brine shrimp are used mainly for rearing  fry.  Adult brine shrimp are used for feeding fish and are available live, frozen and freeze dried.
Asexual- Having no sex or sexual organs, being neither male or female.
Autotomy-  The spontaneous casting off of a limb or other body part, such as a claw of a crustacean.  Normally occuing when an organism is injured or under attack.
Autotrophic- An organism capable of synthesizing (making) its own food from inorganic substances using light or chemical energy.
Bacteria-  Referring to microorganisms found in aquariums and ponds, some are beneficial such as Nitrosomonas and Nitrobacter in breaking down fish waster from toxic ammonium into nitrite into the less harmful nitrate.  Others are harmful and act as pathogens attacking primarily weakened fish and causing dieseases.
Benthic-  Of or relating to or happening on the bottom under a body of water (the seafloor or bottom of a lake for example) dealing with the flora and fauna found living there.
Berlin System- The method of keeping a reef tank with live rock and a protein skimmer as the only filtration techniques employed.
Bioballs- A biological media used in many wet/dry type filters.  Generally made of plastic in a spherical shape with a large surface for beneficial bacteria to colonize.
Biological filtration – the use of media to grow colonies of aerobic or anaerobic bacteria to facilitate the removal of dissolved waste in the form of ammonia and nitrite and conversion to nitrate.
Bioluminescent-  Referring to animals and microbs that are able to produce their own light using chemical processes
Biomass-  Refers to the total mass of living matter within a specified area.  Also sometimes referred to as bioload.
Biomechanical- typically refers to a filter that contains both mechanical filtration and biological filtration all in one unit or at least has the option to portray both capabilities  
Bleaching- The process in which zooxanthellae expel themselves from the tissue of the corals they are living in causing a lack of pigmentation in the coral.  Usually associated with high water temperatures
Blushing – a pink to reddish cast on the fins and tail of a fish indicating stress, often caused by ammonia or nitrite poisoning
Bristleworms-  A polychaete worm that are primarily beneficial detritus eaters.  Once thought to be harmful to reef aquariums most now believe they are benefical to a reef tank as an important part of a clean up crew
Budding-  A from of asexual reproduction where an organism creates a new individual from an outgrowth capable of surviving on its own.
Buffering – waters ability to resist pH changes
Calcareous-  Made or formed of calcium.
Calcification- Impregnation with calcium or calcium salts.  Hardening, as of tissue, by such impregnation
Calcium-  A major element found in natural sea water.  Corals in reef tanks will utilize calcium in building their skeletons and therefore need to be replenished in a closed system.
Carbon (activated)- A chemical filter media used in filter systems to adsorb odors, dissolved organics, pollutants, medications and discolorations.
Carapace-  A hard outer covering or shell made of bone or chitin, such as the fused dorsal plates of a turtle.  Or the portion of the exoskeleton covering the head and thorax of a crustacean. 
Carbonate Hardness-  See alkalinity
Channeling – water running in limited paths and avoiding most of the filter media due to clogging by particulate matter
Chillers-  A water cooling mechanism that utilizes refrigerant to cool an aquariums water as it passes through the unit.  Mainly used in reef aquariums, but can also be used in freshwater and saltwater fish only systems.
Chordates-  Animals from the phylum Chordata having at some stage of develpoment a dorsal nerve cord and flexible spinal column (notochord).
Circum Tropical-  Dealing with areas around tropical or equatorial areas especially waterways
Cnidaria-  Phylum that contains hydras, hydriods, jellyfish, sea anemones and corals.
Commensal-  Of, relating to or characterized by a symbiotic relationship in which one species benefited while the other is unaffected.
Controllers-  Electronic monitoring devices that have the ability to turn on and off other electronic devices when certain parameters are met.  Most popular types of controllers include pH, temperature and Oxidation Reduction Potential (ORP).
Corallimorphs-  Coral like animals from the order zoantharia, commonly called "mushroom corals/anemones" or "false corals"
Coralline Algae-  An encrusting algae that utilizes calcium to grow.  Generally felt to be a sign of a healthy reef tank and desirable.  Mostly purple or red in color, but other colors are found
Corallite- The coral structure or cup formed by an individual polyp in a colony.  Very beneficial in correctly identifying most corals.
Corallum-  The entire coral formed by a colony of polyps.
Cyrptic-  Hidden, concealed or camouflage, as in the coloring of an animal.
Cured Liverock-  Liverock that has gone through the curing process (see Curing liverock).
Curing Liverock-  The process of ridding liverock of organisms that are not able to survive the collecting, handling and shipping of the rock from its collection site to the home aquarium.  
Cyanobacteria-  A photosynthetic bacterium sometimes referred to as slime algae.  Can be seen in a blue green color or red.  Generally considered a nuisance "algae".
Cycling- referred to the process of allowing your aquarium or pond water to go through the nitrogen cycle and grow a specific and necessary amount of aerobic bacteria to create a stable and healthy pond environment
Demersal-  Referring to an organism that dwells at or near the bottom of water.
Denitrators-  A filter designed to remove unwanted nitrates from an aquarium or pond.  Normally accomplished with a slow flow through a media with anaerobic bacteria or via a sulphur-based media.
Detritus-  Accumulated waste material such as fish waste or excess food.
Detritivores-  Organisms that consume detritus.
Diatoms- A single celled algae normally a brown or golden color that will grow on aquarium walls, decorations and sand.  
Digitate-  Having digits or finger-like projections.
Diurnal-  Organisms that are active during daylight hours.
D.O.C-  Abbreviation for Dissolved Organic Compounds.
Drip acclimation-  A method for acclimating newly aquired aquatic specimens to their new environment.  Consists of slowly dripping water from the specimens new home into the water they arrived in to reduce the stress of change in water parameters between the new and old water.
Down-flow systems – filters in which water enters the top and flows down through media and then exits at the bottom of the system
En masse spawn-  An event where all or mostly all of the local inhabitants are simulated to spawn all at once.
Epoxy-  Used to bond or glue rock, plants or corals together.  Most popular types are two part epoxies that harden when mixed together.
Estuary-  The part of the wide lower course of a river where its current is met by the tides of the ocean.  An arm of the sea that extends inland to meet the mouth of a river.  Depending on the tides (low and high) this area can go from saltwater to brackish to freshwater.
Exhalent-  An organ, such as the siphon on a clam, that is used for exhalation.
External pump – a pump that operates outside the aquarium or pond.  
Fallow-  To let lie quiet.  In aquarium usage it is to allow a tank or pond to run with no inhabitants.  Generally this is done to help kill off any parasites that may have affected vertebrates in the tank as there are no hosts for the parasites to live off of.
Family-  A taxonomic category of related organisms ranking below an order and above a genus.
Filter Feeder-  An animal who strain out partiuclate matter, including planktonic life forms from the water column to feed upon.
Filtration system (filter)-  A device that will help purify tank or pond water.  The three main components of a filter system will include mechanical (trapping particles), biological (breaking down of waste products such as ammonia and nitirite) and chemical (adsorbing odors and discoloration).
Fish only system-  Refers to a system with no invertebrates or other organisms contained in the tank, only fish.
FOWLR (Fish Only With Live Rock)- A saltwater aquarium containing fish and liverock, but no coral.
Fission-  An asexual reproductive method (Division).
Flashing – the act of a fish rubbing or scratching their bodies typically to relieve themselves of symptoms associated with parasites or stress
Flocculent – chemical that causes particles such a single celled algae and silt to clump together for easier removal 
Formal ponds – ponds designed in shapes such as circles, squares, and rectangles and conforming to specific design ideas
Fragmentation-  The process of artifical reproduction of corals by breaking, cutting or dividing pieces from the main colony and attaching them to a new base that can eventually become new colonies.  These cuttings are referred to as "frags".    
Frags-  Cuttings of corals from a main colony of coral for the purpose of creating a new colony.  Frags are often traded and sold between reef hobbyists.
Gametes-  A reproductive cell having the haploid number of chromosomes, especially a mature sperm or egg capable of fusing with a gamete of the opposite sex to produce the fertilzed egg.
Genus-  A taxonomic category ranking below family and above species.  Generally consisting on a group of species exhibiting similar characeristics
Glitter Lines (Shimmer lines)-  Light lines viewed underwater on surfaces (such as the sand on the bottom of the ocean) caused by ripples or waves on the surface of that reflect and refract the light from a single source point (i.e. the sun in the wild or a metal halide bulb in an aquarium).
Gravity- fed – flowing into the filter system by the force of gravity and then returned to the aquarium or pond via a pump.
Ground Fault Interrupters (GFI)-  It is a device that measures the amperes (number of electrons) traveling through a circuit and quickly opens (breaks) the circuit if there is a small loss or ground fault to prevent you or your livestock from getting shocked.
Head height – usually calculated in feet, the amount of height a pump pushes against gravity through tubing to the highest point of re-entry into the system. Especially important to know when determining the correct pump for your water feature 
Heater-  An electronic device that will heat water to a specific temperature.  Best used with a controller.
Herbivore-  An organism that eats plant material as its main source of nutrition.
Hermaphrodite-  An organism that possesses both male and female sexual organs
Heterotrophic-  Refers to an organism that cannot synthesize its own food.  It is dependent on complex organic substances for nutrition (heterotroph).
Horizontal or Cross flow systems – flow of water through a filter by entering one side, flowing across media, and exiting the opposite side of the unit.
Hydrometer-  A device for measuring the salinity or specific gravity of salt water.
Ich-  A common parasite that fish get especially when stressed.  Looks similar to salt grains (small white spots) when seen on fish.  There are many different treatments for Ich.  Generally not deadly to the fish unless it goes untreated
Infauna-  Aquatic animals that live in the substrate of a body of water, especially in a soft sea bottom (sand or mud substrate).
Informal ponds - ponds designed without strict geometric form
Intertidal-  The region between the high tide mark and the low tide mark, referring to the organisms that dwell in this area.
Invertebrate-  An animal lacking  a backbone or spinal column
Jaubert System-  Named after Dr. Jean Jaubert.  A filtration system/method used in reef aquariums.  It consists of a deep bed of  sand over a buried plastic plate.  Beneath the plate is an area void of sand with a pocket of unoxygenated water known as a plenum.  Nitrogenous wastes are broken down as the aquarium water diffueses through the area.
Kalkwassser (lime water)-  A saturated solution of calcium hydroxide used to raise the calcium levels in a reef tank.  Available as a powder that is mixed with RO or RO/DI water and dripped into the tank.
Laminar-  A thin scale or plate like structure.  Sometimes used to describe flow (laminar flow) which refers to a unidirectional flow in a flat, horizontal plane.
L.P.S-  Abbreviation for Large Polyp Stony coral.
Liverock-  Rock that has been collected from marine environments used as decoration and filtration in marine fish only and reef tanks.  It will contain micro and macro flora and fauna beneficial to the aquarium.  It is collected in areas such as Fiji and the Marshall Islands.
Livesand-  Aragonite based sand that has micro and macro organisms living on and in the sand that are beneficial to a marine aquarium.
Macroalgae-  Refers to alga that are not microscopic and are many times used in refugiums in saltwater aquariums.  Some examples include Caulerpa and Chaetomorpha.
Mantle-  The flesh or tissue of mollusks.  
Marginal/emergent plants – plants which grow in or around the edges of the pond. Their leaves and stems rise above the water line and they grow rooted in a submersed soil. Typically their crown is not submerged any more than a couple inches below the water.
Meroplankton-  Any of various organisms that spend part of their life cycle as plankton.  Most commonly the plankton state occurs during the larval or egg stages.
Microalgae-  Algal forms that are only visible with the use of a microscope.
Monitors-  Electronic devices that are able to read different water parameters such as pH, temperature and ORP.  They differer from controllers in that they do not have the ability to turn on or off other devices, they only display the values.
Morphology-  A branch of biology that deals with the form and struture of organisms without the consideration of its function.  The form and structure of an organism or one of its parts.
Motile-  Mobile or movable.  Moving or having the power to move spontaneously.
Mutualism-  An association between two different species of organisms in which each organism benefits.
NanoPlankton-  Very small plankton, especially plankton composed of organisms measuring from 2 to 20 micrometers
Necrosis-  The process of tissue dying off; Death of cells or tissues from injury or disease.
Nematocysts-  A capsule within a specialized cell of certain colenterates (such as jellyfish) containing barbed, threadlike tube that delivers a paralyzing sting when propelled into attackers and prey.  Sometimes also referred to as "stinging cells".
Nitrogen cycle – a naturally occurring chemical process by which organic wastes in conjunction with wastes from fish are converted by aerobic bacteria to nitrite, and then in turn are converted again by aerobic bacteria to nitrate.
Nitrosomonas bacteria – a specific type of aerobic bacteria that converts ammonia into nitrite
Nitrospiralis bacteria – another specific type of aerobic bacteria that converts nitrite to nitrate
Nori-  A type of dried seaweed used to wrap sushi.  Also used to feed herbivours fish such as Tangs.
Ocellated-  Having one or more pairs of eyespots.  Theorized to be used to confuse any possible predators.
Octocoral-  A member of the phylum Coelenterata (Cnidaria), class Anthozoa characterized by normally having eight tentacles on each polyp.
Oolitic-  Rock, usually limestone, composed of oolites.  A small round calcareous grain found, for example, in limestone.
Operculum-  Platelike covering over the gills in fishes to help protect the gills.  
Order-  A taxonomic category of organisms ranking above a family and below a class.
Organic load – a term referring to all animal and plant life in a system; primarily fish and decomposing organic matter
Oscula-  The mouthlike opening in a sponge that is used to expel water.  Also referred to as the osculum.
Osmoregulatory system – the system that provides blood to carry oxygen throughout the fish’s circulatory system
Osmosis-  Diffusion of fluid through a semipermeable membrane from a solution with a low solute concentration to a solution with a higher solute concentration until there is an equal concentration on both sides of the membrane.
Ostia-  A small opening or orifice.  Any of the small openings or pores in a sponge.
Oxidation-Reduction Potential (ORP)-  Measured in millivolts (mV), it is the measure of the ability of the water to break down waste products in the tank.  For aquariums the recommended level be between 350-390 mV.
P.A.R.-  Abbreviation for Photosynthetically Active Radiation.  Used in measuring the light levels or energy given off by a lamp.
pH – the measurement of free hydrogen ions in water measured on a scale from 1.0 (acidic) to 14.0 (alkaline).  pH is a contraction that stands for pondus Hydrogenii (weight of hydrogen).
Parasites – small animals that use fish as a host organism for survival. Micro-parasites are observed with the use of a microscope and include trichodina, costia, ich, etc. Macro-parasites can be seen by the naked eye and include lice, anchor worm, etc.
Pathogen-  An agent that causes disease, especially a living microorganism such as a bacterium or fungus
Pelagic-  Of, relating to or living in open oceans or seas.  Ocean-going or "pertaining to the sea".
Photoperiod-  The amount of time the day lights are on over an aquarium. 
Photosynthesis – the process by which carbon dioxide and water are transformed in the presence of light and chlorophyll into carbon-containing, organic compounds in which oxygen is a by-product
Photosynthetic-  That which uses the process of photosynthesis to live and gain energy through utilization of sunlight.
Phylum-  A primary division of a kingdom, as of the animal kingdom, ranking next above a class in size.
Phyto-filtration – the use of plants to remove excess nutrients from the water and aid in particulate settlement; also referred to as vegetative filtration
Phytoplankton- Minute, free-floating aquatic plants.  Microscopic algae suspended in the part of the water column that is penetrated by light.
Pinnules-  Lateral branches (feather like or plume like) on the tentacles of a soft coral that give it a feather-like apperance.
Pipe run- typically calculated in feet, the amount of pipe that a pump is pushing water through to its eventual destination.  Helpful when used in conjunction with head height, to determine the correct pump for your water feature or pond.
Piscine-  Fish-Like or fish.  Of, releating to or charateristic of fish or fishes.
Planktivorous-  Referring to organisms that feed upon (eat) plankton.
Planktonic algae – single-celled, free-floating algae that can make the water appear thick and green like pea soup
Planulae-  The flat, free swimming ciliated larva of a coelenterate.
Powerhead-  A water pump that is submerged inside the aquarium or pond to add extra water movement within the tank or pond.
Predation-  The capturing of prey as a means of mainting life (for nutrition).
Propagation-  The process of multipication or increase in numbers, as by natural reproduction or fragmentation.
Protein Skimmer (Foam Fractionator)-  A filter that removes organic waste from a saltwater aquarium.  Water and tiny bubbles are mixed within a column.  The organic waste is attracted to the bubbles creating a foam (skimmate) that flows into a collection cup.
PVC-  Abbreviation for Polyvinyl chloride.  Tubing used for plumbing an aquarium or ponds pumps and/or return water lines.
Quarantine tank (hospital tank)-  A tank set up separate from a main or display system used to house new or sick fish or invertebrates.  Mainly used to prevent spreading diseases into an established aquarium or pond.  Fish will generally be quarantined for 2-4 weeks before introduction to the main tank or pond
Radula-  A flexible tonguelike organ in certain mollusks, having a row of horny teeth on the surface.
Rapid Tissue Necrosis (RTN)-  Characterized by the rapid loss of tissues on corals generally caused by a pathogen.  Generally will result in the sudden death of corals.
Reef tank (system)-  A marine aquarium consisting of corals and other invertebrates.  Most will also have "reef safe" fish also.   They require high intensity lighting and very good water quality. 
Refugium-  An area or refuge where micro-orgainisms can live and breed without the worry of predation from fish or other organisms.  Also many times macroalgaes will be kept in the refugium to aid in waste (nitrate and phosphate) removal from the aquariums water.
Regenerate- To regrow, for example a starfish can regenerate limbs that have been lost.
Respiration – the process of obtaining energy from organic material, in effect the opposite of photosynthesis, performed by plants during nighttime hours with the by-product carbon dioxide
Reverse Daylight Photosysynthsis (RDP)-  Term used for running a refugiums light opposite of the lights on the main display tank.  Can help to maintain a more stable pH in the tank.
Reverse Osmoisis or Reverse Osmosis Deionization units (RO or RO/DI)-  A filtering unit that purifies tap water for use in aquariums.  Using a series of cartridges (sediment, carbon and with deionization) along with a membrane they are able to remove 95 to 99.8% of contaminants found in tap water.
Rhizome – horizontal underground stems from which roots and shoots develop
Salinity-  Measure of total salts in a given weight of seawater expressed in parts per thousand (ppt).  Also see Specific Gravity
Scute-  A horny, chitinous or bony external plate or scale.  Also called a scutum.
Sedentary-  Refers to animals or organisms that remain or live in one area.  Attached to a surface and not moving freely, such as a barnacle.
Sedimentation-  The act or process of depositing sediment.  
Sepia-  The liquid that is exuded b a squid or octopus called "ink".  Composed of a highly concentrated solution of the pigment melanin and mucus and tryosinase.
Sessile- Permanently attached or fixed, not free-moving.
Settling tanks – usually conical in shape; used before the bio-filtration unit in systems to settle out solids with slow-moving water; typically gravity fed units
Siphon-  A tubular organ, especially of aquatic invertebrates such as squids or clams, by which water is taken in or expelled.
Slough-  To shed.
Specific Gravity-  The ratio of the density of a given solution to the density of pure water.  Natural seawater generally has a SG of 1.025-1.026 on coral reefs.
Spicules-  A skeletal element in soft corals (needlelike in appearance) composed of calcium carbonate.  Also found in sponges made of silicon dioxide.
Spirulina-  A microalgae used in many foods for fish.  Has been shown to help boost immunity in fish.
SPS-  Abbreviation for Small Polyp Stony corals (Acropora and Montipora for example).
Subclass-  A taxonomic category of releated organisms ranking between class and an order
Submerged plants – plants that grow fully underwater
Substrate-  Refering to the layer of stone or sand found on the bottom of an aquatic habitat.
Sump-  A low-lying place, such as a pit (or in aquatic terms anything that holds water) that will receive drainage.
Surface to air ratio – the amount of surface area of pond water not covered by aquatic plants or ice if applicable.  
Symbiotic-  A close, prolonged association between two or more different organism of different species that may, but does not necessarily, benefit each member (Symbiosis).  One of the most famous symbiotic releation ship is the clownfish and anemone.
Tategoi - a koi that has not reached its full potential a koi not yet “finished”.
Taxa-  Plural of Taxon.  A taxonimic category or group, such as phylum, order, family, genus or species.
Taxonomy-  The classification of organisms in an ordered system that includes natural relationships.
Trace elements – minerals needed by plants in small quantities to thrive 
Turbidity-  Relating to the visibilty within a body of water, more turbid water will have more suspended particulates floating in the water column.
Up-flow system – water is introduced at the bottom of a filtration unit and then gravity is utilized to allow water to travel up through the media to an exit at the top of the system
Vascular-  Of, characterized by or containing vessels that carry or circulate fluids such as blood, lymph or sap through the body of an animal or plant.
Water hardness – the concentration of calcium and magnesium salts in the water
Water quality – the chemical balance of water; usually referred to when discussing levels of ammonia, nitrite, nitrate and pH in a system
Zooplankton-  Plankton that consists of animals, including the corals, rotifers, sea anemones and jellyfish that drift in the water column.  Most are microscopic.
Zooxanthellae-  Algae that live in a mutually beneficial relationship with invertebrates.  They take up waste and carbon dioxide and provide the corals with food (fixed carbon or sugar).
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Approved Comments...
perfect for vocab lol homwork done:) Approved: 2/20/2008
Article Details
Created on 7/23/2007.
Last Modified on 7/24/2007.
Last Modified by Sean McWherter.
Article has been viewed 7581 times.
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