Brightwell Aquatics

CoraLazarus - High-Purity Calcium Reactor Media 5 kg

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Discontinued by Bulk Reef Supply
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  • High-purity natural mineral that may be employed in traditional calcium reactors, or even blended in to pre-existing aquarium substratum, to gradually increase and maintain the calcium concentration and alkalinity in marine aquaria.
  • Strong source of calcium, the most abundant cation by percent mass in aragonite, the mineral secreted by reef-building organisms to form skeletal material.
  • Through dissolution, provides calcium, magnesium, strontium, potassium, and carbonates.
  • Aids in increasing alkalinity to stabilize pH and encourage rapid biogenic aragonite
  • formation.
  • Optimal average particle size for use in media reactors and calcium reactors.
  • Free of chloride and sulfate.


Instructions and Guidelines

Rinse material in freshwater or saltwater prior to initial placement in aquarium system. Employ in a calcium reactor per the manufacturer’s instructions. If employing NēoMag, refer to the instructions on the label. The rate of water flow through the reactor in conjunction with the pH of the water inside the chamber(s) will have the greatest impact on the rate of media dissolution. Follow the manufacturer’s instructions furnished with the calcium reactor to adjust the rates of water flow and CO2-injection and attain the desired concentrations of calcium and alkalinity in the effluent.

Measure alkalinity, calcium, and magnesium concentrations in the aquarium two- to four-times each month to ensure that parameters are within the desired ranges, and make adjustments to reactor system as required. As the biomass of corals and other reef-building organisms residing within an aquarium increase with time, so the biodemand of calcium, magnesium, and carbonates increases, as well; this being the case, the frequency at which CoraLazarus must be replaced will increase. Note that each reef aquarium has unique calcium requirements, and that it is possible for the calcium demand in the aquarium to exceed the rate at which this element is liberated from the CoraLazarus material. In such cases, additional calcium supplementation (such as with Brightwell Aquatics Calcion or Kalk+2) may be required to (re-)establish a natural seawater calcium concentration. Another option is to employ a larger (or additional) calcium reactor to house a greater amount of CoraLazarus.

Technical Background

Controlled dissolution of aragonite within a reaction vessel has become one of the most effective and preferred methods of increasing and maintaining the calcium concentration, as well as the alkalinity, in reef aquaria with high-rates of calcification. In particular, high-energy reef systems dominated by small-polyp stony corals, as well as those with heavy coralline algae growth, can benefit from this method, the results being increased growth rates (relative to many other approaches) when all other physical and chemical requirements are met. Aditionally, this method of calcium/alkalinity supplementation is free of chloride, which can become elevated in aquaria utilizing chloride-based calcium supplements if regular partial water changes are not performed.

By weight, CoraLazarus is comprised of ~61 - 62% carbonates, ~37 - 38% calcium, ~0.75 - 0.85% strontium, ~0.1% magnesium, and <0.01% potassium; these percentages may vary between samples. It is collected in a clean environment and does not originate in bivalve-dominated reefs, the aragonite from which tends to be high in phosphate relative to aragonite formed by non-bivalves, in general. There is little magnesium in natural aragonite, and as such it is imperative that magnesium supplementation be employed in reef aquaria utilizing a calcium reactor. Failure to maintain magnesium at a minimal concentration of 1,290 ppm may result in difficulty maintaining the desired calcium concentration in the aquarium. One solution is to employ Brightwell Aquatics NēoMag (~13% magnesium by weight) in conjunction with CoraLazarus. NēoMag may also be used in secondary chambers of calcium reactors to help eliminate free CO2 that has not reacted with CoraLazarus, thereby simultaneously reducing the propensity for pH to exist at a depressed level in the aquarium and increasing the rate of media dissolution, and hence magnesium supplementation.

More Information
UPC 810086014125
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Product Questions

What pH does Brightwell media like to dissolve at? Is it low like the Triton media?
Question by: Justin Hester on May 14, 2020, 5:50 AM
Brightwell calcium reactor media dissolves best at a PH of 6.5 - 6.6.
Answer by: Chad on May 15, 2020, 8:41 AM