Glossary of Common Pond Terms

Aquascape – A small pond used to grow aquatic flowers and other decorative plants.

Aquatic Surfactant – Chemical compounds that decrease surface tension between water and other liquids, solids, or gases. Used with herbicides and algaecides to increase penetration and effectiveness.

Beneficial Bacteria – Strains of aerobic (oxygen-loving) bacteria that help break down nutrient pollution and debris in pond water through nitrification.

Check Valve Assembly – An automatic valve that allows fluid to flow in one direction while preventing backflow.

Cyanobacteria/Blue-Green Algae – Photosynthetic microorganisms related to bacteria that split water molecules into hydrogen and oxygen. Some species produce potent toxins that harm humans and animals.

Fake Rock Covers/Faux Boulders – Hollow fiberglass rock sculptures that conceal and protect pumps, wells, and other outdoor equipment.

Fish Kill – A term referring to poor water conditions causing the death of all or most of the fish in a pond.

Flocculant – Chemicals that promote the clumping of particles suspended in a fluid for easy removal.

Hypoxic/Anoxic Dead Zones – Terms describing areas of water with low (hypoxia) or no (anoxia) dissolved oxygen where aquatic life cannot survive.

Ich Fish Disease - Ichthyophthirius multifiliis, a parasitic disease in freshwater fish that is often fatal, characterized by white spots resembling grains of salt.

Muck – A slimy layer of organic debris and detritus that accumulates on pond and lake bottoms.

Nitrogen Cycle – The natural cycle of nitrogen moving from the soil and water into the atmosphere and back through processes like nitrification, nitrogen fixation, ammonification, and denitrification.

Nitrification – The oxidation of ammonia to nitrite by Nitrosomonas bacteria, then nitrite to nitrate by Nitrobacter bacteria, as part of the nitrogen cycle.

Patio Pond – A small, contained pond suitable for patios and balconies.

Pond Aerators – See Pond Aerators

Pond Conditioner – Products that balance ponds by detoxifying chlorine, chloramine, ammonia, and heavy metals, making the water safe for fish.

Pond De-Icer – A compact heating device used to keep a gas exchange hole open in a frozen pond.

Pond Dredging – The act of using heavy machinery to scrape muck and sediment from the bottom of a waterbody.

Pond Filters – See Pond Filters

Pond Liner – A watertight barrier that prevents pond water from seeping into the surrounding soil.

Pond Pumps – See Pond Pumps

Pond Test Kit – Water testing kits to check parameters such as pH, nitrogen, ammonia, and phosphorous levels.

Pond Underlayment – Thick, soft material placed between a pond liner and the soil to protect the liner from damage and enable gas to escape from the soil.

Pond Vacuum – A specialized vacuum cleaner that uses a solids pump to suction muck and debris from a pond. Pond vacs can usually handle debris up to 3/8”.

Pondless Water Feature – A stream, fountain, or waterfall that pumps water from an underground basin instead of an open pond.

Thermal Stratification – The process of water forming layers of different temperatures due to cold, dense water sinking while warmer water rises to the surface.

Thermocline – A transition layer of cold water that separates the bands of water caused by thermal stratification.

Turbidity – The quality and measurement of the cloudiness of water containing suspended particles.

Water Garden/Garden Pond – A small-to-medium-sized decorative pond, often planted and stocked with ornamental fish, such as koi.

Waterfall Spillway – The opening in the front of a waterfall that allows water to flow into the pond.

Waterfall Weir – A structure in a waterfall unit that raises the water level and controls the volume of water able to crest the spillway.

Pond Aerators

Aerating Fountain/Surface Aerator – A floating aerator that draws water from beneath the surface and sprays it into the air, where it oxygenates before returning to the pond.

Bottom Diffused Aerator – A submerged aerator that releases air bubbles into the water to promote oxygenation and circulation.

Solar Pond Aerator – An aerator that uses photovoltaic cells to power pumps and compressors for off-grid use.

Water Circulator – A submerged apparatus that churns and circulates water using a propeller.

Windmill Pond Aerator – A supplemental aeration system that harnesses wind to power pumps and compressors.

Pond Filters

Filter Media – A layer of material in a filter that allows water to flow through while trapping debris, often inoculated with beneficial bacteria for biological filtration.

Gravity Filter – An external pond filter that uses gravity to move water through layers of filtration media before returning the water to the pond.

Pond Bio Filter – A biological filter for ponds that uses beneficial bacteria to clean the water at a microscopic level.

Pond Ionizer – A device that uses a computer chip to slowly release copper ions into the water to control filamentous (string) algae growth.

Pond Skimmer – A filter that rests on the surface of a pond to remove large floating debris like leaves and twigs.

Pond UV Clarifier – A tube containing a high-intensity ultraviolet light that destroys the DNA of planktonic algae (green water) and other harmful microbes present in water that passes through it.

Pressure Filter – An external pond filter that pumps pressurized water through filtration media for rapid cleaning.

Submersible Filter – Sometimes known as a pre-pump filter, this submerged filter removes debris from water before it enters the pump.

Waterfall Filter – A combined biological and mechanical filter housed inside a waterfall unit.

Pond Pumps

Aerator Pump – A compressor or diaphragm pump that transports air into a pond.

External Pond Pump – A high GPH water pump that sits outside the pond and uses tubing to move water.

Fountain Pump – A pump housed in a fountain enclosure that draws water up through the base and pushes it through the spray nozzle.

Solids Pump – A water pump that allows small solid particles to pass through.

Submersible Pond Pump – A low GPH water pump that sits inside the pond, skimmer, or waterfall vault.

Water Feature Pump/Waterfall Pump – A selection of pumps used to transport water from basins to waterfalls or water features like spitters.