Seawater chemistry refers to the natural composition and balance of dissolved elements and compounds found in ocean water. It’s the benchmark reef keepers reference when mixing salt and targeting appropriate parameters for a healthy, stable tank.

Conductivity measures water’s ability to conduct an electrical current, which correlates directly with the concentration of dissolved ions, or salt, in the water. It’s the underlying principle behind digital salinity meters, offering a fast and precise alternative to refractometers or hydrometers.

Mineralization is the process by which organic matter breaks down into simpler inorganic compounds, releasing nutrients back into aquarium water. It’s a key part of the nutrient cycle, closely tied to detritus decomposition.

Scleractinian coral refers to the scientific classification encompassing all stony, reef-building corals, including both SPS and LPS varieties commonly kept in home aquariums. This group forms the calcium carbonate skeletons that build natural reef structures worldwide, making it foundational to reef biology.

A nano reef is a small-scale reef aquarium, typically under 30 gallons, prized for its compact footprint and lower initial cost. Nano reefs require careful management, since smaller water volumes leave less room for parameter error.

Source water is the raw water supply, typically tap water, that a reef keeper purifies through reverse osmosis and deionization before using it in a tank. Its quality significantly affects both purification demands and final water chemistry.

Coral stress refers to the physiological strain a coral experiences from unfavorable conditions, such as unstable parameters, poor lighting, or inadequate flow. It often precedes more visible symptoms like bleaching or tissue recession, making early recognition valuable.

Solubility refers to how much of a given substance can dissolve into aquarium water before it reaches saturation and begins precipitating out. Understanding solubility helps explain dosing limits and precipitation risk in reef chemistry.

A coral frag is a small fragment cut or broken from a larger coral colony, capable of growing into an independent colony of its own. Fragging is central to reef keeping, letting hobbyists propagate, trade, and share corals without harming wild reefs.

Montipora is a diverse genus of SPS coral known for its wide range of growth forms, from encrusting plates to branching structures. It’s popular among reef keepers for its relative hardiness and striking color variety.

A skimmer cup is the removable collection container atop a protein skimmer that captures concentrated organic waste, or skimmate, as it overflows from the reaction chamber. Regular cup emptying is a routine but essential maintenance task.

A coral feeding schedule is a planned routine for how often and how much food a reef tank’s corals receive. Establishing a consistent schedule helps match nutrition to actual demand, supporting healthy growth without overloading the system with excess nutrients.

Molybdenum is a trace element involved in certain enzymatic processes within reef organisms, present naturally in seawater at very low concentrations. It’s rarely tested or dosed directly, typically appearing only on comprehensive ICP reports.

Coral bleaching is the process by which corals expel their symbiotic algae, causing them to turn white or pale. It’s typically triggered by stress from temperature swings, light changes, or poor water quality, and can be fatal if the coral doesn’t recover its algae in time.

Molecular binding refers to the chemical attraction between molecules or ions, a concept underlying processes like chelation, adsorption, and filtration media function. It helps explain how various reef tank chemistry and equipment interactions occur.

Two-part dosing is a widely used method of supplementing calcium and alkalinity through two separate liquid solutions, dosed daily to replenish what coral calcification consumes. It’s one of the most accessible ways to maintain stable major elements.

A cryptic zone is a dark, low-flow area of a reef tank, often within a sump or beneath rockwork, where light-avoiding filter feeders and microfauna thrive. It adds biodiversity and supports natural nutrient processing beyond what the display tank alone provides.

Natural seawater is ocean water collected directly from the sea, sometimes used in reef keeping as an alternative to synthetic salt mix. It offers a complex natural composition but requires careful sourcing to avoid contamination risks.

Coralline algae is a calcifying algae that grows as a hard, encrusting layer across rock, glass, and other surfaces in a reef tank. Its pink, purple, and red coloration is widely considered a sign of a healthy, well-established system.

Euphyllia is a genus of large-polyp stony coral known for its long, fleshy tentacles and vivid coloration, encompassing popular types like Torch, Hammer, and Frogspawn corals. Despite its stony skeleton, its soft, waving appearance and potent sting mean careful placement is essential.